Bridgestone Motorcycle Parts Discussion Board

Bridgestone Tech Talk => 175 & 200 Talk => Topic started by: al_pritchard on December 15, 2014, 04:32:13 PM

Title: Racer Resurrection
Post by: al_pritchard on December 15, 2014, 04:32:13 PM
Thought a quick introduction was in order as I start to resurrect this mighty beast of a race bike. I'v just acquired a new to me BS 175 that was previously raced with AHRMA. It's hasn't been on the track for a couple of years I think, having suffered a catastrophic crank failure - you can see in the pics below. The good news is it came with a cash of 2 spare cranks. One NOS, never run and the other in good form with the oil pump gear already removed.

Having never changes from when I was a kid. The first thing I did when I got it home was to take it apart and see what we had to work with. I knew the crank was bad when I bought it, and had assumed that some internal case damage and piston damage had occurred. Pulling the jugs relieved small ghosting in the chrome on the left barrel. That was easily honed out and the bearings moved from one crank to the other. Everything else in the bottom end looks exceptionally clean. I think I lucked out!

But I do have some general questions.

1. Can someone identify the modification to the rotary covers? They are larger than stock, and do not have the razed mount for the oil pump.

2. Has anyone ever seen these carb covers? The previous owner mentioned that he acquired some race parts and I assume this is one of them. How common were these, and are they factory or after market.

I need to order up a set of pistons, the only spare I don't have.

Getting it home
(https://farm8.staticflickr.com/7557/15843180598_8e64de26c5_z.jpg) (https://flic.kr/p/q91rCb)

Engine detail
(https://farm8.staticflickr.com/7551/16004831556_9c1ff53036_z.jpg) (https://flic.kr/p/qohWPE)

The inside
(https://farm9.staticflickr.com/8642/16030607995_ac431da945_z.jpg) (https://flic.kr/p/qqz4g2)

Right rotary cover
(https://farm8.staticflickr.com/7517/15844865097_b8b0123eb1_z.jpg) (https://flic.kr/p/q9a5ng)

Up-raited carb
(https://farm8.staticflickr.com/7543/15410976813_786cc6660f_z.jpg) (https://flic.kr/p/ptPhuM)

They look trick
(https://farm8.staticflickr.com/7489/15844570539_301261844d_z.jpg) (https://flic.kr/p/q98yNF)

(https://farm8.staticflickr.com/7477/16004841766_41fa20a5c5_z.jpg) (https://flic.kr/p/qohZRG)

More at https://www.flickr.com/photos/loft42/ (https://www.flickr.com/photos/loft42/)

Title: Re: Racer Resurrection
Post by: OldSwartout on December 16, 2014, 09:32:13 AM
The rotary valve covers, carburetors and side covers are the factory SR175 racer parts. All are very rare, although there are probably a few pieces stashed in people's garages that occasionally show up on e-bay.  The bike also has an SR alternator (aluminum center section, no windings for battery charging) and appears to have something other than the stock points ignition system since the alternator end cover is spaced out from the body.

The bike may have SR cylinders or standard DT cylinders, you'll have to measure the parts you have. Either bore could be used in AHRMA. Don't buy pistons and rings until you've determined which you need.
Title: Re: Racer Resurrection
Post by: bsracer on December 16, 2014, 09:54:13 AM
Looks like Karl beat me to my post. I was going to say to measure the pistons as the SR175 has 49mm and stock 175 is 50mm. Be interested to know the history as i've never seen that one before.

Also the LH inner crank appears to be "blued" in the pic. Are the rods 180 from each other?

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on December 16, 2014, 10:16:18 AM

Thanks Karl, Paul,

As to history, the last time it was raced was at Grattan. This is where it spun the con rod - causing the blue. Im not sure what year that was, but it was a couple of years ago. I cant seem to find the old results on the AHRMA website.

It was previously owned and raced by Dave Dunfey as a trial bike while he was putting together his Vincent. When it wrapped the rod I think he moved over to the Vincent. Cant blame him, beautiful bike.


I'll need to do a second measurement to be sure, but over the weekend we measured 1.970". So that looks like it indicates a DT bore and not an SR. I didn't get a set of pistons with the bike, or spares - I suspect they got lost over the years.

1.970" = 50.038mm
1.965" = 49.911mm

And no Paul, the rods are not 180 from each other. Luckily I did get 2 cranks in the deal. So one future spare and one to rebuild.
(https://farm8.staticflickr.com/7553/15408352894_f0fdbdc325_z.jpg) (https://flic.kr/p/ptzQuN)

But it didn't seem to damage the casing.
(https://farm9.staticflickr.com/8615/15408354814_3af86c146f_z.jpg) (https://flic.kr/p/ptzR4U)

Thanks for the info on the alternator. My plan was to follow your Dyna S ignition upgrade (http://bridgestonemotorcycleparts.com/index.php?topic=3645.0 (http://bridgestonemotorcycleparts.com/index.php?topic=3645.0)) I wonder if I should look for a DT alternator to do the modification incase someone is looking for a SR alternator.

Title: Re: Racer Resurrection
Post by: OldSwartout on December 16, 2014, 12:07:37 PM
If you're planning on putting it on the street as a cafe bike or ?, you would want to change the alternator. Of course you'll have to wire in a rectifier and a few other wiring additions. You should see what kind of ignition is in that alternator before going too far, you could probably transfer it to a stock one if it is a decent electronic ignition.
Title: Re: Racer Resurrection
Post by: al_pritchard on December 16, 2014, 02:42:40 PM
Karl,

I'm planning on keeping it a race only bike. No streets in it's future. But you make a good point, I need to open it up and get a better idea of what the current ignition is before I start making to many plans.
Title: Re: Racer Resurrection
Post by: OldSwartout on December 16, 2014, 03:48:42 PM
I found Dave Dunfey in the AHRMA results from 2009 and 2011 in the Class C Foot Shift class, which is probably where a Vincent would run. I didn't see anything from the 200GP class or Formula 125, the classes the Bridgestone would normally run. Perhaps the crank let go before he got a finish on it.  There doesn't seem to be archived results prior to 2009.
Title: Re: Racer Resurrection
Post by: BigAl8295 on December 20, 2014, 10:11:09 AM
I hope you have it ready for the AHMRA event at NJMP in July.

Craig Hirko was out there with his last summer and ours is finally running.
Title: Re: Racer Resurrection
Post by: bsracer on December 20, 2014, 11:42:10 AM
In looking at some of your other pics, the cylinder shows 177cc which should indicate the pistons are 50mm. The SR cylinders have that removed. Also looks like an early motor as there are no locating peg for the center bearing and the bearing has oil groove.

paul

Title: Re: Racer Resurrection
Post by: al_pritchard on December 26, 2014, 08:40:59 AM
Not making any promises about running at NJMP for AHRMA or USCRA. July is a stretch goal, September may be more realistic. But I will bring the bike down for review and discussions.

I think some discussions have been had on other threads about pistons, and not running stock pistons.

Vince, in the UK talks about running a KX100 piston at 52.5mm with a re-bore and lining. Then later about a Wiseco 50mm to 52mm from an RM100.

Anyone care to chime in on piston recommendations?

Little more on my plan, and some math - I'll blame this next section on Gordon Jennings tuners handbook (http://www.amrca.com/tech/tuners.pdf (http://www.amrca.com/tech/tuners.pdf))

Should be able to safely make 31 HP at 11,500 RPM with a healthy margin of error up to 12,000 RPM.

I've also been looking at Vince's post about using a Yamaha RD200 head to get the advantage of a squish band. But I'm not sure the legality in AHRMA or USCRA. Any thoughts?

Lots of time on my hands to think about this stuff while I'm on vacation away from the bike.
Title: Re: Racer Resurrection
Post by: OldSwartout on December 27, 2014, 10:08:07 AM

I think some discussions have been had on other threads about pistons, and not running stock pistons.

Vince, in the UK talks about running a KX100 piston at 52.5mm with a re-bore and lining. Then later about a Wiseco 50mm to 52mm from an RM100.

Anyone care to chime in on piston recommendations?

I've also been looking at Vince's post about using a Yamaha RD200 head to get the advantage of a squish band. But I'm not sure the legality in AHRMA or USCRA. Any thoughts?


My past experience with stock pistons is that the rings didn't live very long when revved to 11,000 regularly.  A couple of us that race the 175's are using Wiseco Suzuki RM85 2nd oversize pistons.  However, to use them correctly, you have to shave the top of the cylinder or run without a head gasket, plus reshape the head to keep a reasonable compression ratio.  The Suzuki pistons have a .035 inch shorter pin-to-top distance and a flatter top.  The Suzuki pistons require another .005 inch clearance to keep from seizing, so can't just be slapped into a stock cylinder.

I'm not certain that you need a Yamaha head for the squish if you use the Suzuki pistons. Here is a normal BS 175 SR head that provides about 13:1 CR with stock pistons. Below that is a Bridgestone head modified  to maintain the same CR with the Suzuki pistons. Since the head has to be cut so much due to the flatter top of the Suzuki piston, squish is pretty easy to control when machining the head.
Title: Re: Racer Resurrection
Post by: bsracer on December 27, 2014, 10:28:16 AM
Hi Al,

I run Wiseco Suzuki RM85 pistons that are 50mm in my 175 racer.  AHRMA has limitations on the carb size (22mm) and a max overbore of about 1.5mm for gp200. Vince has different rules to allow 52.5mm and has a iron liner. I have the cylinders nikasil plated. These bikes have transmission and crank weaknesses. I took my bike to the dyno once and their dyno could not read the ignition (old ignition) so I don't have a hp figure.

I've worked on the trans the last few years and it is much improved. I still want to hard chrome the shift fork tips as I don't have any new ones. Since I broke another crank earlier this year, that's the first thing on the list to fix. Maybe after that, I'll try and get it back to the dyno.

paul

p.s. I think you have to plug the holes and re-drill the RD heads
Title: Re: Racer Resurrection
Post by: OldSwartout on December 27, 2014, 10:45:09 AM
Paul and I have broken numerous crankshafts and Craig Hirko has broken at least one. I'm not certain about others that have raced the 175. Vince has the answer on that; better center bearing support. The transmissions like to jump out of gear. I never fixed mine, just lived with it, Paul has made progress on the stock trans, Vince is using an expensive aftermarket special. Like racing any stock street bike, especially vintage ones, they all have their weak points.
Title: Re: Racer Resurrection
Post by: vinny g on December 27, 2014, 01:53:31 PM
Hello Al.
To clarify a few points..i run the KX100 piston at 52.5 in ceramic coated cylinders that are far superior to nicasil items.As Paul says we do have different rules here and can run at full 200cc..in fact i can run at 54mm if i need to as thats 1mm oversize on the 200cc Bridgestone that is eligible here.
The RM100 piston(50mm type Wiseco454) is around 1mm taller pin to crown and the peg needs moving.Dependent on the tune id just jack the cylinder up on a gasket.
Theres much to be said for choosing which parts you are going to run and building an engine around those parts,as Karl says theres usually a bit of skimming etc involved.
In my experience the Wisecos are a fit and forget proposition though keep an eye on the ring pegs bedding inwards with miles.
The cranks can be made to last even without a fourth bearing..but a straight pin is a nescessity.I havent broke one yet.
Transmissions are a pain..the reality is new gears need making with a decent undercut on them,something thats impossible with round dogs/gears.
Karls head mod is ok though..as long as the end result is what you need how you get there is of no consequence.

 Vince
Title: Re: Racer Resurrection
Post by: bsracer on December 27, 2014, 02:39:47 PM
Hey Vince,

Thought you were running cast iron sleeved cylinders. Are you using Apticote 2000 ceramic from Poeton Industries? I think they have someone here in the states that does that application.

paul
Title: Re: Racer Resurrection
Post by: vinny g on December 27, 2014, 03:08:33 PM
Hi Paul. I run both cylinders..the 54mm are on liners and i have a pair of lined ones im setting up for the RM100 piston. Current engines with the KX100 52.50 piston are coated with Apticote.Highly recommended.I found that the cylinders would "bed in" when i had them nicasiled and leave a wear edge at the top of the cylinder.Almost as if the cylinder had withdrawn if you like.The Apticote cylinders are still showing the original hone marks after two years use.

The best set up (for me) has been the Apticote cylinders running kx100 pistons.I suspect that should i have a pair of 200 (Mach11)cylinders plated and run with a decent piston then power will go up again..ive managed to get much more transfer area using those.

Vince
Title: Re: Racer Resurrection
Post by: al_pritchard on December 31, 2014, 09:07:48 AM
Thanks for the guidance and input. 

Karl, thanks for the pics and insight into your setup. And thanks Paul for confirming piston options. 

Just to confirm before ordering, the second oversize is a 49.00 mm RM85 piston. Part#: 806M04900 (https://www.wiseco.com/ProductDetail.aspx?ItemID=806M04900&ModelID=313&ModelYear=2004&AppID=3995 (https://www.wiseco.com/ProductDetail.aspx?ItemID=806M04900&ModelID=313&ModelYear=2004&AppID=3995))

While we're on the subject of pistons, any recommendations on wrist pins and wrist pin bearings?

Al
Title: Re: Racer Resurrection
Post by: bsracer on January 01, 2015, 11:17:59 AM
I'm not sure of the actual RM85 oversize but I use the Wiseco 806M0500 which is a 50mm piston. I think the kits now come with ring (1969cs), cir-clips (cw14) and a wrist pin (s288). I use the Wiseco B1012 wrist pin bearing (top end bearing) which I order extras of. Like Vince said, you want to get everything lined up before you go ahead with the motor. I've had cylinders nikasil plated at Millennium Technologies. I think it was around $175 per cylinder last time I had them done. There is a place in Wisconsin that does the ceramic plating that I think Vince is talking about called Max Power RPMs. Looks like they charge around $225 a cylinder. I may give them a call after the holidays to find out more about the process.

paul
Title: Re: Racer Resurrection
Post by: Jmw on January 31, 2015, 10:05:20 PM
I am the owner of a 175 that has seen much better days, I also have what my wife calls a sick obsession with older racing bikes. The 175 in question has the right piston seized but the crank is free, i have no carbs and the clutch seems to be toasted. I would like to build this with the intention of racing it someday, if or when that will happen is questionable (we all gotta have dreams). If using the rm85 pistons is it only the head that needs to be 'altered' or does the top of the cylinder need the same treatment. Also is the portion removed strictly the 1 mm raised gasket area on the head or is there some machining of the combustion chamber. I am in need of carbs as well and was curious if the mikuni vm18-144 would work. I don't have any original carbs to take measurements and wanted to know if those new mikuni carbs were even an option.
Marcus
Title: Re: Racer Resurrection
Post by: OldSwartout on February 01, 2015, 10:22:11 AM
I machined the top of the cylinder .035" to compensate for the roughly .035" shorter distance from the pin to the crown on the Wiseco Suzuki piston vs. stock. I order to get the higher compression ratio (approx. 13:1) while using the stock head gasket, I machined the head to 7.2 cc volume (see photo in reply #10 in this thread). Unfortunately, I can't find my note as to how much that actually was in linear measurement, you'll have to measure with a syringe & plate. You can see the squish that I ended up with. That was a 15 Deg. cut.

Paul Piskor (bsracer) did his slightly differently to get similar results with the Wiseco pistons. He was running without head gaskets, I believe, and may not have cut the top of the cylinders.
Title: Re: Racer Resurrection
Post by: bsracer on February 02, 2015, 10:34:01 AM
My cylinders were set up for a "zero deck height", the piston comes flush to the top of the cylinder. The RM85 pistons being shorter, the material was taken off the bottom of the cylinders (base). I run Tab Loc (pre-DG) aftermarket heads. They are high compression (somewhere I have notes!). The bike never ran with well set up this way so I made base shims and run it as I did before with the piston not coming up all the way and no head gasket. I really should find out the corrected compression ratio. After I get this crankshaft stuff sorted, I will get some heads done with a proper squish. I also have a box with a clutch that I had a Kawasaki KX125 clutch basket converted to fit the BS driven gear that is about 1 pound lighter than than BS clutch. I just need to finish it!

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on February 03, 2015, 08:07:45 AM
My thinking for cutting the top off the cylinder instead of the base was that, with the shorter piston, the port opening/closing point was increased by .035" on all the ports. I don't know if that was good or bad, but that was my reasoning. I still opened up the exhaust port more anyway.
Title: Re: Racer Resurrection
Post by: al_pritchard on February 03, 2015, 09:48:56 AM
Paul - I’d be very interested in seeing your notes around your head design. One concern I had with the BS head, is it doesn’t seem to have a lot of meet in the dome. And I didn’t want to cut to deep into it.

I would have assumed the same as Karl regarding taking off material from the base of the cylinder.

I’m still a little new to this engine tuning and measuring. But needing as a place to start I had a session with the degree wheel this weekend. I don’t know if my ports are stock, or if Dave made any modifications to them. But the rotary inlet port in the side of the case has been modified.

Sorry, my degree measurements were horifiy wrong, so I've removed them to prevent confusion. I'll re-measure this weekend and re-post.
Title: Re: Racer Resurrection
Post by: bsracer on February 06, 2015, 12:30:33 PM
Hi Al,

I will look for those notes. I think I mainly checked the volume of various heads I have. I've had a couple sets of stock milled similar to Karl's. The TabLoc heads came with a squish but they are 1960's technology. I have a set that I got from an old racer that look like they were welded up pretty nice and a proper squish cut. However I haven't measured the volume yet and a bunch of the fins got broken off in shipping. One of the other things on the list of mods is to have some heads done to with a proper squish. If you want to give me a call with questions 619-675-4060. I'll dig up my timings or at least what I have written down somewhere.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on February 06, 2015, 03:06:30 PM
Thanks Paul,

Heads will be the next serious investigation for me. I wanted to get the cylinders out of the way first and work the heads while they were sent out. I'll take you up on your offer for a call soon.

In the mean time I spent some time with the degree wheel and a nice pint last night. Looks like I’v got a "half-speed" alternator. Good to know as I start looking at options for an electronic ignition.

In preparation for having my cylinders nikasild I wanted to better understand the current port timings, and make any alterations. This includes decking the cylinder based on the heigh of the new pistons, and any alterations to port sizes.

An interesting thread over at NATs on a 350 GTR is talking about  adding transfer gullies between the transfer ports and host port. They mentioned the yamaha TD1-C had a similar setup. It’s considerations like this that I want to take into account before sending off the cylinders to be nikasild.

Along with the port timings below, I’v also done my best to measure the ports. Take it with a grain of salt - I’m sure I’m off by a square mm. But this is what I got.

Port Measurements
Exhaust Port: 501.5 sq mm
Transfer Port 1: 154.5 sq mm
Transfer Port 2: 154.5 sq mm
Boos Port: (need to do this still)

Piston Timings
92° ATDC - Exhaust Opens
112° ATDC - Boost Ports Open (opposite of exhaust)
116° ATDC - Transfer Port Opens
158° ATDC - Bottom of Transfer Ports
170° ATDC - Bottom of Exhaust Port

180° ATDC - BDC

192° ATDC - Exhaust Port Bottom (12° PBDC)
206° ATDC - Transfer Ports Bottom (26° PBDC)
246° ATDC - Transfer Ports Closed (66° PBDC)
250° ATDC - Boost Port Closed (70° PBDC)
270° ATDC - Exhaust Port Closed (90 ° PBDC)

* The bottom edge of the transfer port is cut below the piston top at 90° BDC.

Rotary Timings
40° ATDC - Rotary Inlet Port starts to close
76° ATDC - Rotary Inlet Port fully closed
222° ATDC - Rotary Inlet Port starts to open (24° PBDC)
280° ATDC - Rotary Inlet Port fully open

And because we all love photos.

Cylinder Rubbing
(https://farm9.staticflickr.com/8567/16273006547_f2d7ac83f6_z.jpg) (https://flic.kr/p/qMZpUp)

(https://farm8.staticflickr.com/7332/16457961352_24cc27085d_z.jpg) (https://flic.kr/p/r5kmwm)

Checking my work
(https://farm8.staticflickr.com/7399/16457166761_0e4fba25eb_z.jpg) (https://flic.kr/p/r5ghjv)

And rechecking my work
(https://farm8.staticflickr.com/7314/16272664949_e98c4dbe35_z.jpg) (https://flic.kr/p/qMXEmM)

And the port maps and measurements
(https://farm9.staticflickr.com/8582/16457954052_a61d70c407_z.jpg) (https://flic.kr/p/r5kjmu)
I could not find graph paper with one square equal to 1mm. So I scaled the drawing up, it’s a little easier that way actually. The larger square makes it easier to count.



Title: Re: Racer Resurrection
Post by: al_pritchard on February 06, 2015, 03:54:28 PM
Forgot to add the port map. Again, I’m sure this is not 100%. It was my first time doing this so I suspect I’m off just a little.

(https://farm8.staticflickr.com/7323/16272956269_7f3cb34891_z.jpg) (https://flic.kr/p/qMZ9Xx)


Title: Re: Racer Resurrection
Post by: bsracer on February 07, 2015, 12:48:05 AM
That's funny,

Gerrit from the NL and I are the ones talking about the added ports on the NATS site. My thought was to add another port between the transfer and boost port that feeds between the two. I also thought of welding up the transfer base and making the transfer bigger to feed the added port between the boost and transfer. My problem is I have no idea if or how it would work. I think I've seen something like it in another cylinder at some point but don't remember what bike. Like you, I try to plan as much out beforehand. I can give you a pretty good list of things that need to be improved before you spend any cash on making it faster!

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on February 07, 2015, 10:13:39 AM
Here are photos of SR cylinders and one of the pistons off my 175 roadracer with added port area. I don't know who did this work, I ended up with them on the bike when my brother Jim helped resurrect it in 2002 from storage after 25 years in the barn. He rode the bike to 2nd in 200GP at the Daytona AHRMA races in 2003. Additional area could be obtained by ports between the transfers and boost as you're discussing. Unfortunately, these were damaged during the 2004 season and I went back to modified standard cylinders.


Title: Re: Racer Resurrection
Post by: bsracer on February 08, 2015, 11:13:34 AM
Wow Karl,

Thanx for posting pics. I've seen finger ports added to cylinders over the years but never anything like that!

paul
Title: Re: Racer Resurrection
Post by: Gerrit on February 09, 2015, 05:21:09 AM
I am at a loss to explain how these extra channels could work positively. While they do add transfer passage capacity, the streams are directed in a purely vertical direction and would disrupt the flow pattern from the mains and booster in my opinion.
I was thinking of extra gullies between mains and booster, like the gullies Yamaha added to the TD1-C cylinders. These did work on a TD1-C and were 12 mm wide and about 3 mm deep. Unfortunately I have never had my hands on a TD1-C cylinder to measure the gullies for both dimensions and flow direction. The distance between mains and booster on a GTR is about 15 mm chordally according to a quick measurement, so there is space to add gullies which are 10 mm wide. Whether they would have a positive effect on power is quite another matter, however.
Title: Re: Racer Resurrection
Post by: OldSwartout on February 09, 2015, 09:47:40 AM
I agree Gerrit, the flow disruption might be detrimental.  However, the bike ran pretty good that weekend. He was only beaten by Dennis Poneleit on his Honda 175. Dennis, in his 70's, is still winning the AHRMA 200 GP class on that same bike bike 11 years later.
Title: Re: Racer Resurrection
Post by: al_pritchard on February 10, 2015, 09:07:53 AM
Paul I would be very interested in seeing that list.

A fare amount seems to have been done to the bike based on the Bridgestone tuning book. But I think some could have been done a little better. So any guidance would be very appreciated.

Karl, thanks for posting those cylinders. My wife happened to be looking over my shoulder when I was reading you post. As she often does when I’m looking at bike stuff - I think it’s to keep me from spending to much. Her comment was “Holy s*$#, you need to do that? Seems a little risky.”

The idea of adding something similar to the “S” port of the TD1-C is interesting. They mention the cooling benefits to the cylinder by allowing the trapped gasses to move out more efficiently. Being replaced with fresh cool gas. There is the oiling benefit to the to pend bering to think about as well.

I wonder if our RM85 piston will allow for the additional port. I’m out of town so I can’t look at all the parts, but the RM85 has a recess just above the ristpin. And use the TD1-C style port, the piston needs to have a port added.

(I’m still new to all this, so I tend to follow established patterns at this point. If you don’t think the port in the piston is necessary please tell me. Just be prepared for me to ask why.)

I couldn’t find any pictures online of the TD1-C but my copy of Yamaha Two Stroke Production Roadracing Motorcycles by Greg Bennett has a chapter with a couple of images. (I highly recommend this book by the way. Loaded with detail on the production bikes.

Lets start with the TD1-C Cylinder
(https://farm9.staticflickr.com/8581/16304030778_15b5e91c29_c.jpg) (https://flic.kr/p/qQJqjW)
Not the best pic, but you can see the “S” port in the upper right of the cylinder

And it’s matching piston
(https://farm8.staticflickr.com/7376/16490753782_75fc8f7eaa_c.jpg) (https://flic.kr/p/r8eqz5)

The book also has a picture of a “special” cylinder and matching piston. This cylinder had “A very rare TD1-C cylinder. Note the transfer port directly below the secondary transfer rather than an open S-shaped boost port which was the case with most TD1-Cs” (quote from above book.)

TD1-C “Special” Cylinder
(https://farm8.staticflickr.com/7408/15871813003_7233fcd3ec_c.jpg) (https://flic.kr/p/qbxc3k)

And it’s matching piston
(https://farm9.staticflickr.com/8586/16490753672_a6e4c62a75_c.jpg) (https://flic.kr/p/r8eqxb)

And the TD1-C Port Map
(https://farm8.staticflickr.com/7376/16305824477_350caa49ac_c.jpg) (https://flic.kr/p/qQTBwM)


The port map and cylinder pictures are from the above mentioned book that can be found at http://www.tz350.net/yamaha_two_stroke_production_roadracing_motorcycles.htm (http://www.tz350.net/yamaha_two_stroke_production_roadracing_motorcycles.htm)


Title: Re: Racer Resurrection
Post by: bsracer on March 03, 2015, 10:01:30 AM
Hi Al,

here is a copy of what I sent to a guy in New Mexico that is building a couple of Bridgestones for customers. Sorry I didn't get back sooner. I got the rods I ordered from the NL and they aren't what I thought they would be. Also the place I was going to use in AZ for the crank work (Crank Works) is backed up with the start of the new race season. I'm probably just gonna use a back up stock crank until I can figure out a permanent fix.

    

   

Joe Ackley
Hi Joe,

Here is a picture of the rotary valve covers that I had done. Originally the Bridgestone covers are not equal length. I had these made to be the same length. If you modify stock ones you can probably make them the same length. If you want to run a Dyna ignition off the crank you would have to modify the rotary cover. The other photos are of a bike that was raced since new by Dwaine Williams. He did lots of mods over the years. Sadly he passed racing his Norton at Barber in 2007. As you can see of his bike, the carbs can get out there pretty far.

The last pics are of my bike with MX100? Yamaha carbs (22mm) and a shot of my current ignition mounting. I guess there are a lot of mods that I due that i just don't think about.

Add three extra clutch springs to keep clutch from slipping. I work at a Jaguar shop and I found a spring from a V8 cam tensioner that slips right over the Bridgestone spring.

I replaced the pins in the shift forks with solid ones and hand ream them to fit. Pain in the ass but at the time I was having all kinds of transmission problems.

Gears have all been undercut.

I had a new shift selector cam gear made to have more  positive shift. I copied the profile from a late 90's Zx10 kawasaki and had it altered from 6 to 5 speed. Then I had someone draw it up (then had some samples water jet cut) and we varied the profile to have a couple of different peak heights. I went with a pretty aggressive one and added a roller bearing like the ZX10.

I run Suzuki RM85 Wiseco pistons (806M05000) that are 50mm. This is an oversize for the RM but the same size as stock bore for 175 Bridgestone. I have Millennium Technologies Nicasil plate the cylinders. I run them just a tad looser, wiseco recommends .0020 clearance, i use .0025.

I've broken several cranks. A friend and fellow Bridgestone racer Karl Swartout (engineer) had some new center crank pins made a few years ago. This was to fix some of the broken cranks we had. I broke one of those last year. The pin is orig part of one half of a center flywheel. He had pins made and bored out the broken center pin. These pins were stepped and the same thing happened. Usually due to the bike running one one cylinder. The new idea is to have a straight 20mm center pin made and eliminate this problem. I talked with Scott Clough yesterday and he was probably going to use the same guy for the cranks. I'm waiting on rods from the Netherlands (Pro-X 1981 RM125)  before I can get started on the crank. The Bridgestone rods are great. The big end bearing kinda sucks though. The rm125 rod is same dimension except for being wider top and bottom. I want to have the material taken off the crank wheels and retain the nice silver cage bearing. I want to take material off the top of the rods to still use the RM85 pistons.

I have had rear sprockets done from a couple of places. PBI should have the profile on file. I use stock front ones (14,15,16) and I found a 13 from something else that I use on really short tracks. I have rears from 34-44 and the way the ratios are, I never use anything below 38 and the chain would hit the brake hub with the 34-35.

The stock brakes are not bad. I've had the brake shoes relined at a local place with two different materials. One is like a standard heavy truck brake lining. The other has a metal weave that takes way too long to bed in and is pretty aggressive on the liner. The bridgestone front braked fine but it was machined thinner (I run 32mm Ceriani forks) and it broke once racing at Barber. I run a Honda CB450 Black Bomber front hub now. It has enough braking to lift the back wheel under heavy braking.

As above I run 32mm Ceriani forks. I had the stem modified to fit the Bridgestome frame and run tapered bearings from ALL BALLS.

The front rim is WM1 40 hole (CB450 is 40 hole) and the back is WM2 36 hole with standard Bridgestone rear brake. There are two types of rear brake hubs. Mine is the 6 hole pattern for the sprocket. There is an earlier version with a separate hub carrier that has only a 4 hole pattern for the sprocket.

I currently run a Bridgestone BT39ss 2.50x18 tire on the front and a Heidenau 2.75x18 on the rear. i use to run the Bridgestones front and rear but they really heat up and the tubes can't take it. I may switch to a Heidenau 2.50 in the front sometime this year.

I had a custom aluminum seat and tank made by a guy in the UK back in 97. Sadly he retired. His workmanship is unbelievable and his prices were cheap! I ditched the seat because it kept breaking. It is very similar to an early Yamaha TD/TZ seat. Kent at Airtech made a fairing, seat and tank for a 175 a few years ago. That is the seat I have now. I really need a new fairing as mine is the original Harley Sprint (as supplied from Rockford Motors) one that has been repaired many times. My tank was very long like the bikes of the 60's era. I had it shortened by a good bit to get weight over the front more.

If I think of more stuff which I'm sure I will, I'll shoot off another email. Feel free to ask anything you may have questions about.

paul
Title: Re: Racer Resurrection
Post by: Gerrit on March 07, 2015, 09:23:38 AM
The extra ports in the special TD1-C cylinder are similar to those in the TR2.The only way to get something similar in GTR cylinders is with completely new castings, or bore out the standard cylinder, carve the passages in and add a sleeve with the extra ports, either cast iron or aluminium. The latter, of course, needs a nikasil coating.
An alternative shape to that of the extra transfers of the TD1-C is that used by tuners in the UK for the Greeves Silverstone; they added a third transfer port above the intake which had, roughly, the shape of an inverted tea-cup handle. I suspect that this shape gives better control over the direction of the gas stream than the TD1-C type gullies. I think I may have a sketch or drawing of this arangement somewhere.
Title: Re: Racer Resurrection
Post by: bsracer on July 22, 2015, 09:58:28 AM
Hey Al, I see you joined the NATS list. How's the project going? I haven't had any time for anything! Haven't found any other Bridgestone notes especially the ones I'm looking for with the jetting on a previous carbs set up. Getting ready to go race at Miller in Sept and Barber in October.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on August 14, 2015, 09:59:03 AM
Hi Paul,

Progress has been slow over the summer. I’m working on a project up in Boston , so traveling back and forth from NJ has had an impact on my “velocity”. That and Iv been waiting for the new tank and fairing show up. When I order it, I thought it would only be a couple of weeks - it was a tad longer. Should be able to fit all the big parts over September, and get the cylinders set out for boring, porting and platting.

Also been talking with Karl about getting a set of his pipes and rotary covers. The pipes I have look similar to the tuning recommendation, but they are rather beat up.

On the subject of fairings and tanks. How has everyone been mounting them? The PO of my frame welded a tube across the top of the frame. You can see it just above the engine. The problem with this, aside from not knowing if it will align wit the fairing is it prevents you from pulling the head of the engine without removing it from the frame. Not an ideal.

Not the bar in the upper right
(https://farm1.staticflickr.com/687/20559439932_e258db2a57_k.jpg) (https://flic.kr/p/xjLvdh)IMG_2255 (https://flic.kr/p/xjLvdh) by Al Pritchard (https://www.flickr.com/photos/loft42/), on Flickr

Also picked up a set of forks
(https://farm1.staticflickr.com/700/20379313670_fc10b943c4_k.jpg) (https://flic.kr/p/x3RiX5)IMG_2157 (https://flic.kr/p/x3RiX5) by Al Pritchard (https://www.flickr.com/photos/loft42/), on Flickr

The old ones are a bit rusty
(https://farm8.staticflickr.com/7695/17826192491_a9f8c4a44d_k.jpg) (https://flic.kr/p/taeTYp)Untitled (https://flic.kr/p/taeTYp) by Al Pritchard (https://www.flickr.com/photos/loft42/), on Flickr

Paul, I think you mentioned on a separate thread you had to turn down the steering tube to find a bearing that would work. I may need to pick your brain on that as well. Once I get the old forks off and get some measurements.
Title: Re: Racer Resurrection
Post by: bsracer on August 22, 2015, 09:13:48 PM
Hey Al, good to hear from ya. Mine has some tabs with captive nuts that we welded to the frame tubes going down to the swing arm. From there ears go forward to a tube that goes out to the fairing. The first attempt broke many times from vibration, crashing etc. Finally welded some tubes at a 45 to the plate and tube and they've never been a problem. I can get the heads off with no problem but still have to take the motor out to remove the cylinders. I also don't have a battery box and my sump sits right about there. Funny, I have the same tommaselli clipons with shims (35mm) for 32mm. If I remember, the bearings from ALL balls were close and we just had to skim the ceriani stem. You have a different set of forks than me. I'll look and see if I have any pics to post. Damn, the inlet port in your cases looks huge!

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on August 28, 2015, 10:20:51 AM
Yea, I'm a little worried about the port size as well. I' also very worried about how tall the port is. It's hard to see in the photo, but the arched top is very close to the top edge of the rotary disk. Air leeks may be a problem. But I'm working with what I started with, the PO had opened the ports up already. Although they weren't exactly round and smooth.


The New Port
(https://farm1.staticflickr.com/572/20764966449_224ef0b2bb_z.jpg) (https://flic.kr/p/xCVT5V)

The Old Port, Overplayed
(https://farm1.staticflickr.com/741/20941834692_9fd94501bc_z.jpg) (https://flic.kr/p/xUynRo)

Outlines of Both Ports
(https://farm6.staticflickr.com/5625/20329281744_6a42d7f965_z.jpg) (https://flic.kr/p/wYqTcE)

Worst case is I need to make custom rotor disks to modify the open and close intervals. Or a new case.

In other news, parts arrived!
(https://farm1.staticflickr.com/702/20951636135_c603705b7d_c.jpg) (https://flic.kr/p/xVqBtM)
I'm slowly taking over my wife jewelry studio.
Title: Re: Racer Resurrection
Post by: bsracer on August 28, 2015, 11:50:41 AM
Is the fairing and tank from Airtech?

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on August 28, 2015, 05:26:49 PM
But I'm working with what I started with, the PO had opened the ports up already. Although they weren't exactly round and smooth.

Worst case is I need to make custom rotor disks to modify the open and close intervals. Or a new case.


No need for a new case or worry about custom rotor disks.  Just use JB Weld to build up material where you need it and rework to what you want.  Rough up the surface with coarse sandpaper, maybe drill some shallow small diameter holes in the surface and fill with JB Weld, rework to the shape you need.  I've used it with good luck.  And if it breaks loose for some reason (unlikely), it is not as hard as aluminum and the engine will probably just eat it with no bad results. It's good for 250° F or higher, which exceeds the intake temps you'll get.
Title: Re: Racer Resurrection
Post by: BRT-GTR on August 29, 2015, 12:41:20 PM
   Al,     Re:- Port height / air leakage.

         A couple of weeks ago I cleaned up the crankcase intake ports on a standard GTR engine, just took the lumps off and smoothed them out , no increase in size at this stage. The metal land at the top edge of the port is only 1 to 1.5 mm wide which seemed very narrow for sealing purposes. However, thinking it through, at the critical time in the compression of the crankcase gases, the valve is fully closed and gets pushed outwards onto the valve cover and  I think this is where the seal is made. Even there , adjacent to the intake stub, there is only 3mm of flat surface on which to seal.
 
   It would be interesting to pressure test the disc valve seal but I don't have the kit. The valves do obviously seal effectively, I'm not aware of any reports or signs of blowback through the carbs but then I've never raced one.  So maybe a combination of close tolerances, oil film and gas inertia work together to seal the intake ports in a similar manner to the crank centre labyrinth seal.
    As long as there is some metal at the top edge of the port I wouldn't worry too much about the port height.
      Brian.
Title: Re: Racer Resurrection
Post by: al_pritchard on August 31, 2015, 01:01:29 PM
- Paul,

Yea it the AirTech faring and tank. Pretty happy with the tank so far. But I’m just starting to look at how to get it mounted. It doesn’t use the two rubber pucks by the neck, but has two threaded bungs about 5in back from. I guess I’ll look at making two tabs on the side of the frame rail and bolting it down.


- Karl,
Yea I thought about JB weld, and a friend brought up another product. Cant remember it, but it’s basically an epoxy product, but with an aluminum base.


- BRT-GTR,
Thats a good point.



On another topic, who is showing up to NJMSP this month for the Garden State Classic?
Title: Re: Racer Resurrection
Post by: bsracer on September 01, 2015, 03:04:38 AM
Devcon.

paul
Title: Re: Racer Resurrection
Post by: craig641 on September 04, 2015, 03:54:08 PM
Al,  I plan to be there with my Bridgestone race bike. Stop by and say hello.
Craig
Title: Re: Racer Resurrection
Post by: OldSwartout on September 05, 2015, 07:45:25 AM
Craig, I see you won the 200GP class at NJMP both days.  I assume that was on the Bridgestone.  Congratulations.
Title: Re: Racer Resurrection
Post by: craig641 on September 07, 2015, 06:08:12 PM
Thanks Karl.  When she runs, she runs real well.  When she doesn't she's horrible.  I backed up my four wins at New Jersey with a miserable weekend at Mosport. I had two broken cylinder studs on Friday.  Followed by a dead battery in one heat race on Saturday and then a connecting rod bearing gave up in my second race on Saturday.  Along with a couple of overcooked pistons.  And I just got back from a race at New Hampshire where I couldn't even get my bike to run for more than about ten seconds.  I'm almost ready to throw in the towel on this thing.
Title: Re: Racer Resurrection
Post by: OldSwartout on September 07, 2015, 08:28:39 PM
There does seem to always be issues with the old two-strokes when trying to push them so far.  I used to race a production GS450 Suzuki in WERA back in the day; it was nice to be able to just go race without something to rebuild between race weekends or sometimes between practice and a race on the same day.  Back then, you just had to tape over the lights and go race, so you could ride the bike on the street during the week (which I did).  The only time I ever wrecked that bike was on the street, not on the track.   ::)
Title: Re: Racer Resurrection
Post by: bsracer on September 08, 2015, 10:27:10 AM
I made it 6 laps on Fri practice at Miller before the big end bearing went. I think I had the timing too far advanced since before Willow.

paul
Title: Re: Racer Resurrection
Post by: vinny g on September 09, 2015, 04:30:43 PM
There's no reason why a Bridgestone can't be both fast and reliable.We have no real issues over with them over here and do no more than basic checking and maintenance.In 15yrs i've never had one seize.Over the last few years a broken ignition wire and a snapped stud are my only dnf's.

Make sure you press your cranks up so the big end's are exactly in the centers of the bores.I've measured a few that press together a mm or so out and that will fry a big end as the rod/bearing scuffs the crank cheek.

Use a quality 2 stroke oil..and plenty of it.Go fully synthetic at 27:1.

We used Bridgestone standard cranks reliably upto 11000rpm and 32 rear wheel bhp.

Watch for air leaks on the crank drive side..it's possibly to get a leak along the splines and drive gear.Clean the outer face of the gear..smear with silicone..smear along the splines..fit flat washer..fit nut..tighten.A smear on the faces of the bush will do no harm either.

I don't run paper base gaskets,the mating faces aren't wide enough.Once you know the thickness you require make them in alloy or steel.Silicone both sides..Threebond is ok.

If using a standard LH discvalve housing only run a single lipped seal.A double lipped leaves the outer un-lubed without an oil pump and it will overheat the seal.

Vince
Title: Re: Racer Resurrection
Post by: vinny g on September 09, 2015, 04:33:21 PM
Oh..and a 6mm hole in the piston skirt just below the ring land inline with the rear boost port will vent hot gasses and keep the piston crown cooler.
Title: Re: Racer Resurrection
Post by: bsracer on September 10, 2015, 11:09:32 AM
Thanx for the input Vince. I usually run Maxima 927 Castor at 28:1. Have aluminum shims for base gaskets. Never had an issue with the LH seal but will look it over. I also seal the RH gear as I noticed leaks when pressure testing in the past. This was strictly my fault for not being thorough. I advanced the timing a couple of races ago along with another change. That change didn't work and I didn't move the timing back. This time out, again the bike showed signs of being rich. The change to 32:1 did not seem too drastic. The fact that the timing was still advanced did lead to the big end failure. I still consider to have never "seized". Bores in good shape . The crank locked solid on the bearing that failed. Very interesting to see the bottom end, the cylinders and the head completely dry of oil and no real damage aside from the big bearing. I will have it back together for the next race at Barber in Alabama in October, with a little more attention to detail.

paul

p.s. keep me posted on those parts Vince!
Title: Re: Racer Resurrection
Post by: al_pritchard on September 22, 2015, 10:36:42 AM
Paul - Thats the stuff I was thinking about.


I had the fortune to meet Craig last weekend at NJMSP. I was a perfect late summer day for spectating - and racing I’ll bet. It was a blast watching Craig chase a pack of bigger bikes, nipping at there heals. I suspect it’s quite unsettling being chased by a little 200cc machine. Craig added a little drama on Saturdays second race, stalling at the start. A clever technique to put the bigger bikes at ease and lower there guard.

I also want to thank Craig for letting me poke around his bike, and ask questions. I think he gave me what I will take as the best advice so far - “Run the stock cylinders for the first season while you get the bike sorted and settled. And look for a 2nd set of cylinders to port”. So that’s the updated plan.

I’ll have lots more questions coming up, but for the moment let see some pics.


Starting to test fit the fairing and tank
(https://farm1.staticflickr.com/666/21004707093_7fef63f8b5_c.jpg) (https://flic.kr/p/y17BCi)

Looks like I may need to cut, and reattach the head brace
(https://farm1.staticflickr.com/701/21438909719_06d0bfe6a1_c.jpg) (https://flic.kr/p/yEu1Wt)
It was installed by the previous owner and is 45* to the head, not parallel to the ground.

I’ll also need to do a little bit of modification to the faring to accommodate the bigger carbs
(https://farm1.staticflickr.com/648/21003002484_b0c715460f_c.jpg) (https://flic.kr/p/xZXSUu)
Craig needed to do this as well, and I would have likely missed it if not for seeing his bike this weekend.

And a view of the cockpit
(https://farm1.staticflickr.com/735/21438018498_89116c719f_c.jpg) (https://flic.kr/p/yEps1A)
Title: Re: Racer Resurrection
Post by: craig641 on September 24, 2015, 09:53:27 AM
Al - just something to think about.  In your sideview picture it shows that your ass is going to be placed almost directly over your rear axle.  That's going to put an awful lot of weight to the rear of the bike, that's going to affect your handling.  Probably not a lot you can do about it if you're going to use that long tank.  Also if you keep your seat in that spot and your footpegs where they are located that's going to put your feet forward of your hips by a lot when you're sitting on the bike.  That won't be comfortable for your riding.

Craig
Title: Re: Racer Resurrection
Post by: al_pritchard on October 06, 2015, 09:32:59 AM
I’m afraid your right Craig, but I may not be able to completely correct the situation. I think the wife will kill me if I go buy a different tank at this point. It looks like the flange of the top and bottom molded parts are joined with a substantialy thick lip that extends almost two inches past the internal space of the tank on the top. If you look closely at the tank you can see the lip. I’m going to have a good look inside the tank today and get on the phone with airtech to see if some of that can be trimed off. If it can I think it will go a long way to moving the tank and me further forward. If not… new tank or longer swing arm sometime down the road.

I’m not to worried about the body position in regard to foot and hip placement. It doesn’t feel to bad sitting on it. Although 5 minutes in flip flops standing still is a lot different than full race gear and time.

Shameless Selfe
(https://farm1.staticflickr.com/711/21599639706_c5a11c6251_c.jpg) (https://flic.kr/p/yUFNn9)

On another note. I’m starting the process of adapting my new triple clamp and forks. I’m wondering if any of you remember the bearings sizes or part number you ordered. Paul mentioned he had to skim the stem to make it work for him. But I think he may have a different triple clamp.

The races I pulled out of the Bridgestone neck are 47.60mm / 1.874in wide. And the stem on my new clamps is 26mm. The challenge, aside from finding a bearing with the correct outer diameter and bore diameter. Will be fitting the bearing in the upper neck cup. As it is only 5.5mm deep, I’m assuming that the bearing race will extend above the neck.

Bridgestone triple clamp on the right
(https://farm1.staticflickr.com/687/22003114691_5e0fb5a677_c.jpg) (https://flic.kr/p/zwkHqp)

Neck Measurements
(https://farm6.staticflickr.com/5649/22003345351_cb8f11c1d6_c.jpg) (https://flic.kr/p/zwmTZi)

Did anyone get different measurements? I'm using a rather cheep digital caliper so I suspect it may be off.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 26, 2015, 03:31:49 PM
Ordered the bearings from Allballs to attempt the conversion to taper bearings. So far, so good.

NOTE: I’m not using the Bridgestone steering yoke, so keep that in mind as you follow along.

99-3509-5 (25mm x 48mm x 13mm) for the top bearing. I selected the 13mm tall bearing for the top. Because I was a bit worried about having the bearing and race extend so far above the top of the neck.

99-3505-5 (25mm x 48mm x 15mm) for the bottom. The recess in the bottom of the neck is much deeper than the top and I wanted to make sure the bearing was tall enough.

Both races fit nice and snug into the neck. Put’s my ability to use calipers at questions based on the last posting.

Next up will be skimming the neck on the new yoke.

Steering stem dimensions:
Top of the stem, with threads: 25.32mm (0.997in)
Body of the stem: 25.92mm (1.020in)
Internal diameter of the stem: 18.55mm (0.730in)

I’ll need to remove a little.
Top of the stem, with threads: 0.36mm (0.015in)
Body of the stem: 0.96mm (0.038in)

Top Race
(https://farm6.staticflickr.com/5700/22485815572_771f5985bd_c.jpg) (https://flic.kr/p/AfZFzo)

(https://farm6.staticflickr.com/5669/22499235855_f93054dbb0_c.jpg) (https://flic.kr/p/AhbsXz)

Bottom Race
(https://farm1.staticflickr.com/647/21876495024_9952576843_c.jpg) (https://flic.kr/p/zk9KNG)

(https://farm1.staticflickr.com/733/21876847584_1efcb9a363_c.jpg) (https://flic.kr/p/zkbyBj)

Fork Yoke
(https://farm6.staticflickr.com/5785/21805442248_10dcd7362f_c.jpg) (https://flic.kr/p/zdSAhQ)
Title: Re: Racer Resurrection
Post by: al_pritchard on November 02, 2015, 11:01:48 AM
A little more progress over the weekend.

With the bearings fit, we skimmed down the steering shaft just a bit to get it to fit the 25mm bearing. Didn’t need to take a lot off. The threads are a bit more square, but plenty of thread still left to hold. (Click image below for video)
(https://farm1.staticflickr.com/575/22714638265_8870274af5_c.jpg) (https://flic.kr/p/ABdsAe)

The entire set up fees much more solid than the original roller bearings. Both smoother to turn, and more solid feeling. I was able to use the bearing dust cap from the Bridgestone for the top. I’ll need to look around for a solution for the bottom bearing. And I’ll need to remove the old steering stop at the bottom of the neck.
(https://farm6.staticflickr.com/5701/22711340515_04822ef666_c.jpg) (https://flic.kr/p/AAVyht)

(https://farm1.staticflickr.com/748/22722524831_06a663c2cb_c.jpg) (https://flic.kr/p/ABUSZv)

(https://farm6.staticflickr.com/5833/22685329196_583f8643b8_c.jpg)

Next steps will be to address the Bridgestone front hub, and the Ceriani axle. Speaking of the axle, does it look like it’s sticking out a little far? I’m wondering is its not the correct axle.
[url=https://flic.kr/p/ABUUa6](https://farm1.staticflickr.com/583/22722528751_ba8941cbee_c.jpg) (https://flic.kr/p/AyCf2s)

I also did some trimming on the tank to see if I could get it a little further forward. Craig mentioned earlier about my body position in relation to the rear hub. I managed to get the tank about an inch forward. Every little bit helps. Brackets for the tank and faring are all ready. Just need some time with the welder.
Title: Re: Racer Resurrection
Post by: rwgibbon on November 02, 2015, 05:18:20 PM
Al,

I give you a lot of credit. You have skills well beyond what I have.

It is great to see what a real mechanic is able to do.

Thank you for posting your progress.

Randy
Title: Re: Racer Resurrection
Post by: slawsonb on November 02, 2015, 05:38:49 PM
i agree, Randy. Pretty awesome.
...bert
Title: Re: Racer Resurrection
Post by: al_pritchard on November 09, 2015, 08:56:16 AM
Don't oversell me here guys. I'm just hacking my way through this.

The real mechanic is a busy of mine who "guides" me to the better solution. He did a lot of work on snow machines back in the day, so he got a little 2 stroke knowledge.  ;D
Title: Re: Racer Resurrection
Post by: slawsonb on November 09, 2015, 11:05:38 AM
Modesty appreciated. I'm sure many of us have been fortunate enough to have a mentor who helped with and taught skills. I, for one, am enjoying watching this. Nice project Al. Don't sell yourself short.
...bert
Title: Re: Racer Resurrection
Post by: bsracer on November 10, 2015, 11:08:58 AM
Looks good so far Al. I think I did basically the same thing to mine as yours (stem). I need to recheck the steering head tube of the frame as I think the upper bearing race has become loose (after 12 years of racing!).

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on November 30, 2015, 03:22:10 PM
Quick update for the Thanksgiving weekend. Mucked around with the front hub and axle this weekend.

The Bridgestone front axle measures just under 15mm, and the new to me forks use an axle that is just under 12mm. So I’m thinking I’ll need to machine up a new axle shaft, as the Bridgestone one is no long enough. This will also require me to drill out the axle hole in the lower left fork to accept the larger diameter axle.

Paul, I think you mentioned that you needed to machine your hubs to accept the axle on your forks. Employing that you are / were running a significantly thicker axle than the Bridgestone. I wonder if you and I have different forks - mine are suppose to be Ceriani 32mm.

Bridgestone on the bottom
(https://farm6.staticflickr.com/5706/22802076883_d550809342_c.jpg) (https://flic.kr/p/AJWB3B)

The new axle will need to be as thick as the Bridgestone, and as long as the Ceriani.

Anyone have any thoughts about materials? I think I have some stainless steel lying around that may be long enough.
Title: Re: Racer Resurrection
Post by: bsracer on December 03, 2015, 10:24:14 AM
I think back when we did mine I had access to a good amount of other motorcycle parts. There is probably some axle from another bike that is close to fitting. At one point we extended the head portion of the BS axle by welding a piece of tubing then turning it to fit the ceriani fork. The Bridgestone 175 brake plate was machined thinner to fit the ceriani forks and a new spacer made to center the wheel. There wasn't enough material and the brake plate broke on me at Barber back in 06 or 07. I run a Honda CB450 Black Bomber front wheel now. It is a bit bigger diameter and the brake plate has a thicker boss. Enough stopping power to lift the back wheel in certain conditions (racing in a parking lot!).

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on December 30, 2015, 09:18:04 AM

As we approach the new year, a year I won't be traveling. It's time to refocus on the bike in 2016.

Next order of business is a new set of rims. I pulled the old dry rotted tires off the other week and found a fare amount of rust. So aluminum is in my future. Any one have opinions on rim brand selections?

Excel rims are nice, but very pricy. Not that it's not worth it, just wondering if there are more reasonable rims that people are trusting on a race bike?

I keep seeing posts that some Borrani rims are now manufactured in Italy, and not just drilled there. But others seem to be skeptical. Not that they are that much cheaper.

Any thought or recommendations?
Title: Re: Racer Resurrection
Post by: bsracer on December 31, 2015, 03:14:28 AM
Hey Al,

are these the ones you're referring to? http://www.ebay.com/itm/WM1-1-60-X-18-36-hole-Akront-Italian-style-flanged-alloy-vintage-motorcycle-rim-/161871699509?hash=item25b04e1e35:g:vLQAAOSwo0JWMBzs (http://www.ebay.com/itm/WM1-1-60-X-18-36-hole-Akront-Italian-style-flanged-alloy-vintage-motorcycle-rim-/161871699509?hash=item25b04e1e35:g:vLQAAOSwo0JWMBzs)

i thought these were ok. I'll check with a friend to see if these were the same ones he purchased. He's had no problems.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on January 04, 2016, 01:19:01 PM

They are exactly the ones I was thinking of. Glad they are ok, I don't want to skimp on rims but I'd love to be able to put the money difference to other areas.

Title: Re: Racer Resurrection
Post by: bsracer on January 05, 2016, 02:23:13 AM
I'll call my friend tomorrow and see if these are the same ones.

paul
Title: Re: Racer Resurrection
Post by: bsracer on January 06, 2016, 11:27:16 AM
Hey Al,

I talked to my friend about the rims . He got them direct from Italy because he ordered multiple sets. He said he paid 55 Euro each but this was a few years ago. The company he got them from is Tronconi & Novelli which is Motocicli Veolci http://www.motocicliveloci.it (http://www.motocicliveloci.it). I think these are the same rims as the ones on eBay. You would have to make sure with the seller.

paul
Title: Re: Racer Resurrection
Post by: slawsonb on March 17, 2016, 05:00:05 PM
Sorry for injecting a question into your thread Al, but I too am contemplating aluminum rims. Does any one know what the correct size specification (WM?) is for 350 19" rims? The stock steel DID's outside measurement is ~2.75in and the bead to bead measures ~1.830in. Any help appreciated.
Thanks...bert
Title: Re: Racer Resurrection
Post by: Gerrit on March 17, 2016, 08:08:44 PM
Bert, that sounds like a WM2 rim which is 1.85".
Title: Re: Racer Resurrection
Post by: slawsonb on March 17, 2016, 08:53:39 PM
Gracias, Gerrit. Now back to our regularly scheduled programming.  ;D
...bert
Title: Re: Racer Resurrection
Post by: al_pritchard on March 29, 2016, 03:30:18 PM
I’v been very neglectful of the bike, and updating everyone as of late. So lets see if I can change that, and get the bike moving along faster.

A little work on the frame. The front fairing bracket needed to be repositioned. Steering stops needed to be added - the old frame based stop interfered with the lower fork yoke. And side mounts needed to be added for the fairing.

I found some nylon threaded pipe to hose adapters at the hardware store that are a perfect fit. They slide on tight over the bolts. I’ll drill them later and safety wire them to the fairing mount. Once I fully work out the steering range I want. I seem to recall FIM having a maximum but I don’t expect we need to follow that for AHRMA or USCRA. Feel free to correct me if I’m wrong. Or give me guidance on what you have your steering range is.

Steering Stop and Fairing Mount
(https://farm2.staticflickr.com/1611/25846005630_fca0c5b37f_z.jpg) (https://flic.kr/p/FnVx1J)

(https://farm2.staticflickr.com/1622/25514082454_09c90917f9_z.jpg) (https://flic.kr/p/ESAkPm)

(https://farm2.staticflickr.com/1561/25846003950_540d132b12_z.jpg) (https://flic.kr/p/FnVwvL)

Side Fairing Mount
(https://farm2.staticflickr.com/1556/25514082554_a79a836493_z.jpg) (https://flic.kr/p/ESAkR5)

NHK Stabilizer
(https://farm2.staticflickr.com/1511/26118846495_1f6f87555a_z.jpg) (https://flic.kr/p/FN2V6z)

(https://farm2.staticflickr.com/1647/26118845995_83ebd745e5_z.jpg) (https://flic.kr/p/FN2UWX)

That shinny red stand is good for an extra 5hp
(https://farm2.staticflickr.com/1607/26052492641_fdcdb7f1b2_z.jpg) (https://flic.kr/p/FGaQpB)

As late fall set in in the north east it was time to close down the shop. A particularly sad moment each year, made even sadder as 2015 will be the last full year for me in that shop. The farm it’s on is getting ready to be sold - development marches on. So the bike needed to find a new home, at least a nee temporary one until I can find a new workshop. So home it came. And where else would be more appropriate than the living room. (I love my wife)

Dry and Warm
(https://farm2.staticflickr.com/1489/25516220713_df30f3b496_z.jpg) (https://flic.kr/p/ESMirT)

Period Bike, Period Chair
(https://farm2.staticflickr.com/1549/26118844295_d018d2fcf5_z.jpg) (https://flic.kr/p/FN2UrD)


Now back to where we left off, I was looking for rims. Well I found them. Ended up ordering a WM1 for the front and a WM2 for the rear. The quality looks pretty good, with slight narrowing around the weld area. Overall the seem to be true and I feel comfortable running them at this point. I also ordered stainless spokes and nipples from Buchanan’s. 10a Stainless spokes and 10ga .250 x .790 nipples. Just under $300 for the spokes and nipples and $177 for the rims.

Don’t Forget the Anti Seize
(https://farm2.staticflickr.com/1467/25514072024_8afe01243e_z.jpg) (https://flic.kr/p/ESAhHw)

(https://farm2.staticflickr.com/1640/26052482851_46163b5754_z.jpg) (https://flic.kr/p/FGaMuP)

(https://farm2.staticflickr.com/1522/25514072884_589e303b87_z.jpg) (https://flic.kr/p/ESAhYm)

(https://farm2.staticflickr.com/1554/25516212233_cf1e44f25a_z.jpg) (https://flic.kr/p/ESMfVF)

Building the wheel was relatively start forward. Found lots of tutorials and videos. None stand out as being best. So take a look at a handful if you plan on going down this rout. It’s not to hard. Just go slow and don’t force anything.

Building the Wheel
(https://farm2.staticflickr.com/1484/26118834785_6a443cc495_z.jpg) (https://flic.kr/p/FN2RBF)

(https://farm2.staticflickr.com/1700/26118834215_56f66b0658_z.jpg) (https://flic.kr/p/FN2RrR)

Now it’s time to true the wheel. Picked up a wheel balancing stand from harbor freight, and feel like I need to immediately return it. It’s hard to true a wheel when the stand is out of true.

It’s Not Just the Shaft Click to see video
(https://farm2.staticflickr.com/1680/25514078614_0172d8d259_z.jpg) (https://flic.kr/p/ESAjF9)

The Bearings are Out of Round as Well Click to see video
(https://farm2.staticflickr.com/1691/26052488371_8a8c15cd5a_z.jpg) (https://flic.kr/p/FGaP8Z)

So I’m looking for some new bearings to fix this. I think if I can find a bearing that is big enough. I can overlap the bearings and due away with the outer casings - currently the stand uses a skateboard bearing inside a casing. Then I’ll cut a new 13mm shaft that is true.

Also opened up the brake side fork leg to accommodate the 15mm Bridgestone shaft. The Ceriani forks came off a Penton that used a 12mm axle shaft. Opening the hole was rather simple. I used a 12mm shaft to help align the fork leg. Then tightened the holding bolt a little and drilled.

Drilling is Fun Click to see video
(https://farm2.staticflickr.com/1648/26052491141_10e2076df9_z.jpg) (https://flic.kr/p/FGaPXK)

Now it's on to truing and making a new front axle. Stay tuned...
Title: Re: Racer Resurrection
Post by: slawsonb on March 29, 2016, 04:34:42 PM
The bike looks great on the hardwood, Al! You're a lucky man. My wife let me do my first 350 engine rebuild in the living room. Would probably not allow it now., but that's what the shop is for.  ;D ::) ;D
...bert
Title: Re: Racer Resurrection
Post by: rwgibbon on March 29, 2016, 05:29:31 PM
You have a great deal more talent then I do.

Great looking project.

Randy
Title: Re: Racer Resurrection
Post by: OldSwartout on March 29, 2016, 05:38:32 PM
It's looking really good, Al.

I used Buchanan spokes on my racer after my 40 year old originals started breaking.  Much stronger and better looking.
Title: Re: Racer Resurrection
Post by: bsracer on March 30, 2016, 10:42:52 AM
Looking good Al. I went with some Buchanan SS spokes after missing two races at Miller from a broken spoke.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on March 30, 2016, 01:04:53 PM
I'm doing my best to prevent just that Paul. I also ordered an additional 3 inside and 3 outside spokes and nipples so I don't end up in that same position. If nothing else, I'll have spares for anyone else who seeds them.


Al
Title: Re: Racer Resurrection
Post by: al_pritchard on July 07, 2016, 02:06:31 PM
Lots of time keeps passing by, but it seems like little progress is getting made. Such is life. I’m officially over a year behind now, with my original goal to take the bike to NJMP. AHRMA is at NJMP this weekend, perfect milestone reminder. Not to worry, I’m still focusing on getting there. Just a little later.

So, on to the progress. I’v spent an inordinate amount of time trying to true the rims. I’v yet to succeed. I’v gotten the front rim to 0.03/0.04 - not counting the weld seam that is about -0.08+/-. The problem is the rim is not round - not round as in the height of the rim from shoulder to bottom is not equal all the way around. So it kind of hops up and down. The rear is not much better.

So if any one has a recommendation for an aluminum WM1 and WM2 18” 36 hole.

I’ll be at NJMP for the 2016 AHRMA races this weekend poking around the swap meet. Lets see if I get lucky.

Along with the rims, I’v been working on mounting the fairing. It seems a little short to be honest - cover the pipes and the clip ons need to be under the triple clamps. :-\

I think I’v found a happy balance that gets the bubble up high enough. I’ll need to build a new belly pan, but that should be easy comparatively.


Aluminum Stock
(https://c4.staticflickr.com/8/7297/27507502675_01f0042f27_z.jpg) (https://flic.kr/p/HUK9cv)

Starting to look like a part
(https://c6.staticflickr.com/8/7348/27507502525_64ab3ff6fe_z.jpg) (https://flic.kr/p/HUK99V)

So far so good
(https://c8.staticflickr.com/8/7051/27435244191_fdec7b6b00_z.jpg) (https://flic.kr/p/HNmNgz)

(https://c2.staticflickr.com/8/7146/27507501345_920256719d_z.jpg) (https://flic.kr/p/HUK8Nz)

(https://c2.staticflickr.com/8/7701/27539837393_f7d39f8d06_z.jpg) (https://flic.kr/p/HXASbD)

I’m working on two options for the brace at the top. The bar across the triple clamp would be the cleanest. But then I lift the faring high enough to use the cross bar, the bottom of the leading bubble is higher than the bottom of the triple clamp. So I may need to lower the fairing and use a bent rod from the forward mount point that bends back along the clear bubble.

(https://c2.staticflickr.com/8/7319/28155189625_5997ede67c_z.jpg) (https://flic.kr/p/JTYGXT)

(https://c6.staticflickr.com/8/7299/28155189005_848303109b_z.jpg) (https://flic.kr/p/JTYGMc)
Title: Re: Racer Resurrection
Post by: OldSwartout on July 08, 2016, 05:24:31 PM
Nice fairing mounting.   8)

As for truing the rims, .030/.040 may be close enough, but try setting your indicator on the the tire bead mounting surface from the outside, that's what will determine the tire's relative position and what you will need to be as true as possible.
Title: Re: Racer Resurrection
Post by: al_pritchard on July 11, 2016, 10:38:31 AM
Took a trip down to NJMP this weekend for the AHRMA races. Saturday was not the best weather, but the racing was spectacular. The lemans start for the CB160/CB175 class was a blast to watch. And I learned a very important lessen - pay attention to the flag. Otherwise you will need to thread your way across the track with oncoming traffic.

The 200GP race was a blast to watch as well. And the CB’s bumped up to fill out the grid.

This inspired me to get by posterior back into the workshop on Sunday. I’v been struggling with getting the upper fairing mount behind the bubble to work. If I use a straight bar, the fairing needs to be up to high, and has a tendency to distort the shape.

A way around this would be to use an armature welded to the forward mount. A forward mount armature means I need to use a two peace mount - one of steel to wield the armature and an aluminum tube to reach out to the fairing. If I can use a bar across the yoke, it creates a much simpler system. And removing the fairing is easter.

You can see the two part forward mount in this picture. The steel mount has a bar welded to it to help index it to the frame, keeping it from twisting. And a heavy spring to keep it puled in tight to the mount. The aluminum bar/tube mounts to that with a pin.

(https://c1.staticflickr.com/9/8756/27625982264_ae79494f0d_z.jpg) (https://flic.kr/p/J6do43)

I mocked up a bent bar and some aluminum tubes to see if I could make it work. The bent bar drops the mount point a little, and removed the distortion I was getting in the upper fairing.

(https://c7.staticflickr.com/8/7639/27625982414_4ca0956f4b_z.jpg) (https://flic.kr/p/J6do6C)

(https://c5.staticflickr.com/8/7333/27625982524_f5c70a17a9_z.jpg) (https://flic.kr/p/J6do8w)

(https://c7.staticflickr.com/9/8809/27625982654_5c69860264_z.jpg) (https://flic.kr/p/J6doaL)

With it mocked up, I should be able to finish it next weekend. Just need to drill and tap for a set screw into the - what do you call that aluminum bit in the center of the steering tube that the bar runs through?
Title: Re: Racer Resurrection
Post by: bsracer on July 12, 2016, 11:19:28 AM
Hey Al,

looking pretty good. You may want to mock up the motor with just the carbs on to see how they line up with the lower relief in the faring.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on July 13, 2016, 03:56:25 PM

Hi Paul,

Yea, I suspect a little cutting will be in order. I’v about 6cm between the fairing and the carb. I can try to spread the bottom of the fairing and get another centimeter or two. But I think it’s a loosing battle.

My options are to add a bubble - not very sightly but works well. Or cut a hole and let the filter pod stick out. I’m a little worried about that option. Not fully understanding he affects of air flow across the filter pod. Negating vs. positive air pressure and starving the carb.

(https://c7.staticflickr.com/9/8601/28255922406_a79b3c40b3_z.jpg) (https://flic.kr/p/K3SZiY)

On a related note - what to do about fuel.

Since it looks like I’m still looking for aluminum rims - and not looking forward to spending $325 a pop. I’v been trying to find ways to tighten the budget. One of the ways was to find an economical fuel petcock solution. Pingel valves are pretty and all, but at around $100 for high flow valves…

I stumbled across MPS Racing. (https://www.mpsracing.com/products/MPS/Petcocks.asp) They offer a high flow petcock at a very reasonable price. Think sub $55. Not particularly elegant, and and not offered in the size I need. But necessity is the mother of invention, and a good set of petcocks are a necessity.

Off to eBay and a set of 1/4" Female x Male NPT Mini Shutoff Ball Valves for $9.98. And a set of 1/4 NPT to 1/4 barb fittings for $11.18. Put me at a grand total of $21.16. Shipped!

I don’t plan of storing fuel in the tank, so I’m not that worried about the nylon used in the ball valve. If I need to replace them every season I’ll finally loos out after 10 years. I can live with that.

(https://c3.staticflickr.com/9/8770/28255922306_161c9b5ed0_z.jpg) (https://flic.kr/p/K3SZhf)
Title: Re: Racer Resurrection
Post by: al_pritchard on August 03, 2016, 09:56:20 AM
Starting to think about paint, think of going blue and white. We seem to have a couple of the traditional red and yellow machines already. So why not be a little different.

Is anyone making the “BS” keystone logo? I’d like to get a couple.

I’d also like to get the “??????” if anyone is making them.

(https://c1.staticflickr.com/9/8586/28637163792_2b62af8c08_z.jpg) (https://flic.kr/p/KCyX6j)
Title: Re: Racer Resurrection
Post by: bsracer on August 03, 2016, 11:40:15 AM
Hey Al,

looking good. If at all possible it would be best to have the carb as centered in that protrusion that you already have in the lower part of the fairing. Undisturbed air is the best as far as everyone I have talked to about it. My current fairing is a modified Aermacchi 250 one that Rockford supplied to racers. It fits too close to the carb mouth and that's the only reason I've put holes in the fairing. It looks like you have genuine SR carbs so the bell mouths are turned off. Nothing to clamp the unipod filter. If your fairing came with a belly pan, it may pull the fairing together too much at the bottom when fitted. You probably need to fit the fairing in the proper position first then work around that. I picked up a Airtech TD2 fairing which looks pretty much like yours and it will fit way different then my current fairing

Hiroshi Murata's bike is painted in the blue and white scheme. If you are talking about the Katana logo for "Bridgestone" on the lower part of the fairing I may be able to get some for you.

paul
Title: Re: Racer Resurrection
Post by: moonpup on August 03, 2016, 08:32:23 PM
Starting to think about paint, think of going blue and white. We seem to have a couple of the traditional red and yellow machines already. So why not be a little different.

Is anyone making the “BS” keystone logo? I’d like to get a couple.

I’d also like to get the “??????” if anyone is making them.


Would something like this be of any interest to you?
Title: Re: Racer Resurrection
Post by: moonpup on August 03, 2016, 08:51:59 PM
These are also available.....
Title: Re: Racer Resurrection
Post by: al_pritchard on August 05, 2016, 02:32:27 PM
Hi Paul,

Thanks for the encouragement - ever moving forward.

I have the Airtech Bridgestone fairing. It looks like it may be a little wider than the TD2 (TD22 on the site) fairing that you were talking about. At least the side bubbles look wider. The Bridgestone fairing came with a belly pan. But it has no chance of fitting. Im starting to build a plug for a new belly pan now.


Hey Moonpup,

I’ll send you a message. I’d be interested in that.
Title: Re: Racer Resurrection
Post by: al_pritchard on September 07, 2016, 12:21:21 PM
Slow but steady…

I’v worked up a BS Keystone logo for the tank. It’s not perfect, but I think it will work. Getting a hand full cut in vinyl - both black and white. If I end up with extras, I’d be happy to share them. I’ll also work to upload the Illustrator file, or at least a PDF.

(https://c8.staticflickr.com/9/8045/29523613135_4a0973cb05_z.jpg) (https://flic.kr/p/LYUeAF)

I can’t seem to get the font correct for the Bridgestone name. So if anyone has any leads on what font it is. Or better yet, knows who owns the blue racer that was a Barber in 2015. Let me know. I only found 2 pictures of it, but it looks beautiful. And has the correct bridgestone logo on the fairing.

(https://c8.staticflickr.com/9/8495/29523613015_1632ed4867_z.jpg) (https://flic.kr/p/LYUeyB)

(https://c8.staticflickr.com/9/8055/29523613255_a5b723b064_z.jpg) (https://flic.kr/p/LYUeCK)

Only two photos I could find.

Next up. Finishing up a new belly pan. The one that came with the fairing won’t fit with my pipes, so I’m creating a new one. Fun with foam.
Title: Re: Racer Resurrection
Post by: bsracer on September 08, 2016, 01:47:40 AM
Hey Al,

It's Hiroshi Murata's bike out of Santa Fe NM. I'm trying to build him a couple of motors for that bike! He gave me the Katana Bridgestone logo I have on my tank that's on the fairing.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on September 08, 2016, 09:04:48 AM
Any chance you have a digital copy of that Katana Bridgestone logo Paul?
Title: Re: Racer Resurrection
Post by: bsracer on September 08, 2016, 10:30:53 PM
Hey Al,

I don't but I'm sure he does. I'll see about getting a copy.

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on September 09, 2016, 07:57:42 AM
Here's a similar size logo in .jpg.  I also have it as a vector file in .wmf, .dxf and .dwg line formats that can be easily scaled and/or used to cut decals or stencils.
Title: Re: Racer Resurrection
Post by: al_pritchard on September 20, 2016, 08:40:09 AM
Got to spend a couple of hours in the workshop this weekend.

The Ceriani forks and Penton triple tree required a little more work to finish up. If you remember from back around post #53, we had to skim down the steering shaft to fit the bearings. Thats all working well, but it’s not the only work that needed to be done. The lower fork leg needed to be opened up to 15mm. I wanted to keep the 15mm axle and bearings for the Bridgestone front hub.

The last bit of the puzzle is to make up some spacers to center the Bridgestone hub on the new forks. Interestingly the width of the Bridgestone axle from fork to form is the same as on the Ceriani - 133mm. But the Bridgestone is not symmetrical, meaning the hub sits into the right fork. Not up against it as with the Ceriani.

To get the hub centers I needed to make a 4mm spacer for the left, and 26mm spacer for the right. Note, the spacer on the right needed to have the same profile as the original part to accommodate the seal/dust cover. Needless to say, I was no entirely successful. I’m off by a little.

29.89mm vs. 29.52mm
(https://c5.staticflickr.com/9/8437/29183699204_023143df9f_z.jpg) (https://flic.kr/p/LsS62E)

Should have been 26mm and 4mm
(https://c6.staticflickr.com/9/8545/29185532013_a69315aef8_z.jpg) (https://flic.kr/p/Lt2tRP)


Question to the group. The original spacer on the right of the hub is made of steel. Do you think it’s wise to replace it with an aluminum part? The spacer on the left should be good, as it is not a rotating spacer. But the one on the right will tend to spin on the shaft, as well as allowing the seal to spin on it.
Title: Re: Racer Resurrection
Post by: BRT-GTR on September 20, 2016, 03:50:45 PM
   Hi Al,
           Looks like she is coming on well, great job.
   Just a general engineering observation on your choice of spacer materials. Aluminium should be ok as long as A, it does not spin on the steel shaft (tends to gall and wear quickly) and B, does not have a seal turning on it (seals pick up grit and can soon wear even hardened steel) . In other words use Ali for static spacers and steel for dynamic spacers.
   Then again, I probably over engineer, if weight is your main concern, use Ali but check regularly for wear.
     Brian.
   
Title: Re: Racer Resurrection
Post by: al_pritchard on September 21, 2016, 09:49:15 AM

Thats probably good advice Brian. This making parts thing is a little new for me. So getting some basic schooling never hurts. I think I'll be remaking the right side spacer in steel, and leave the left spacer in aluminum. The left spacer is static against the braking plate, where the right spacer is free spinning on the shaft.

Anything I should think about when selecting a material? I also need to make a new axle shaft, and was planning on using stainless. I know stainless on stainless is not a good idea, as you get galling.
Title: Re: Racer Resurrection
Post by: OldSwartout on September 21, 2016, 10:04:09 AM
Al, once the axle is installed and tightened, the right spacer should be clamped axially against the right wheel bearing inner race and shouldn't spin on the axle.  Personally, for a race bike, I think aluminum would work. Lube the seal surface with a little grease when assembling to minimize wear and it should be good for the duration of a race bike's track time.  It wouldn't be satisfactory for a street bike, however.

You can always hone your machining skills by making a thin steel sleeve for the sealing surface of your aluminum spacer.   :)
Title: Re: Racer Resurrection
Post by: BRT-GTR on September 22, 2016, 06:11:10 AM
        I like the idea of the bi-metal right spacer, Karl --- best of both worlds, light weight and wear resistant.

 With regard to material for the new axle shaft, I would seek some expert (not me) advice. SS is generally not known for it's high tensile properties but new improved grades could be available now. Maybe stick to proven grades of standard HT steel, you don't want that item failing at a crucial moment ::) :'(
 Brian.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 04, 2016, 08:46:35 AM

Thanks for trying to trigger my OCD Karl and Brian. But I’m going to do my best to not try making a duel metal spacer. Only because I see it ending in tears, and a lot of scrap metal.

I’ll take the advice on the axle material, an look for a suitable high strength steel.

Remade the brake torque arms over the weekend, as well as a couple of spacers. Still not perfect, but I suspect being off by 0.07mm is okay for an amateur.

Next task on the front end is to create spacers for the torque arm. The arm is a little to close to the fork in the pictures.

(https://c5.staticflickr.com/9/8406/29480977204_78b1ce70e5_z.jpg) (https://flic.kr/p/LV8Hqq)

(https://c5.staticflickr.com/9/8642/29480976724_30affe11b2_z.jpg) (https://flic.kr/p/LV8Hh9)

I need to go back and have a look at the original rear torque arm. I don’t remember it having an offset when I took my measurements. But the arm I made does not want to line up with the link bolt. I can fore it, but it the bar binds on the bolt if I do. I’m assuming the original arm had a bend in it, that I assumed was not “factory”.

(https://c5.staticflickr.com/6/5767/30074641516_eafe70843f_z.jpg) (https://flic.kr/p/MPAp91)

(https://c5.staticflickr.com/6/5676/30074642036_e90aa79fe1_z.jpg) (https://flic.kr/p/MPAphY)
Title: Re: Racer Resurrection
Post by: OldSwartout on October 04, 2016, 08:57:17 AM
Al, I believe both the front and rear links have a little offset on the stock setup. The stock front torque link has a small offset; you could probably bend the one you made and eliminate the need for a spacer, even though it will be a larger offset.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 04, 2016, 09:40:06 AM
Thats what I figured Karl. Guess that gives me something to do this weekend. :o
Title: Re: Racer Resurrection
Post by: al_pritchard on October 13, 2016, 09:27:01 AM

Spacers are finished on the front end. I’m getting better with the lath, got the spacers to within 0.01mm of my goal - WOOT! I will admit I lapped down to the end. In the end it’s a 9mm spacer at the hub, and a 7mm at the fork leg. This should wrap up all the fabrication on the front end. Just need to rebuild the shocks and Finnish truing the rim - can I tell you how much I hate truing the rim.

Look at that!
(https://c6.staticflickr.com/9/8410/30199785141_23776927cb_z.jpg) (https://flic.kr/p/N1DMYH)

(https://c5.staticflickr.com/6/5504/30169393212_90e3669aa4_z.jpg) (https://flic.kr/p/MXY2vW)

For the rear bar, I didn’t see an offset of any significance with the rear bar. So I figured a small bend to better angle the bar and keep it flat against the break would be good. Looks like I’ll have plenty of clearance for the rear tire, so no rubbing issues.

New rear torque bar on top, old bar below. Old and new front, and spacers as well.
(https://c4.staticflickr.com/6/5756/30199784651_1d4c7a14d1_z.jpg) (https://flic.kr/p/N1DMQg)

(https://c3.staticflickr.com/6/5558/30169396162_c05b82c956_z.jpg) (https://flic.kr/p/MXY3oN)

I also started playing around with some epoxy to make a new fender for the rear. Brought out the exotic materials from a previous project. Should be worth 2hp. :o Also making one from fiberglass - if I understand correctly I can’t use carbon kevlar in AHRMA.  8)

(https://c7.staticflickr.com/9/8408/29988586390_9b5d87cc85_z.jpg) (https://flic.kr/p/MFZkWW)

(https://c1.staticflickr.com/9/8128/29988587080_c6c4837af7_z.jpg) (https://flic.kr/p/MFZm9Q)
Title: Re: Racer Resurrection
Post by: al_pritchard on October 24, 2016, 09:36:21 AM

Fork rebuilding over the weekend. Boy, I don’t think they were touched since they were pressed into service. What a mess.

Draining the forks was simple enough. But didn’t get a lot out - maybe 30cc of oil. The tare down reveled a lot of sludge, but thankfully not a lot of striped or worse out parts. Everything cleaned up and went back together with little drama. Except for removing the old seals. What a PITA.

As part of the rebuild, I made a simple fork oil level gauge. Section of aluminum tubing, section of aluminum hose, and an epoxy syringe. Dried out an aluminum plate and put two locking colors on the tube. Vualá!

If you are in need of parts - or seals - for an old Ceriani fork, you might want to try: http://www.pentonpartsusa.com/4b%208%20sachs%20forks.htm

I picked up 4 seals, two ball bearings and sprints and o-rings. And a pare of new stickers.  ;D

I suspect I’ll have some changes to make in the set up. But I need to get the bike complete, and my gear unhand before I start doing suspension tuning. Until then, the new seals should keep the oil off the floor.

I put about 235cc’s into the fork. After pumping the fork up and down to get the oil circulating, and get the air out, I sucked the oil level down to 15mm below the fork tube top, with the fork fully compressed. It looked like I sucked about 1cm to 1.5cm from each tube. I started with a 30 weight fork oil. Probably to stiff, but it’s a place to start.

Paul, Karl, thoughts or guidance?

And some pictures…

Parts!
(https://c7.staticflickr.com/6/5518/30500431846_d0c1f6b3a7_z.jpg) (https://flic.kr/p/NtdFLA)

New Tool.
(https://c7.staticflickr.com/6/5346/30500431286_d38422db13_z.jpg) (https://flic.kr/p/NtdFAW)

Thats it?
(https://c3.staticflickr.com/6/5785/30500429746_f727af0ba0_z.jpg) (https://flic.kr/p/NtdF9o)

(https://c4.staticflickr.com/6/5582/29903673923_88469bfa24_z.jpg) (https://flic.kr/p/Myu9qT)

All Clean.
(https://c6.staticflickr.com/9/8622/29903673373_81000fd8e1_z.jpg) (https://flic.kr/p/Myu9gp)

(https://c4.staticflickr.com/6/5683/29903672523_94cf65738f_z.jpg) (https://flic.kr/p/Myu91K)
Title: Re: Racer Resurrection
Post by: OldSwartout on October 24, 2016, 06:06:36 PM

 I started with a 30 weight fork oil. Probably to stiff, but it’s a place to start.


I was racing with stock forks using 30w oil.  That would be a good starting point on the Ceriani's.
Title: Re: Racer Resurrection
Post by: bsracer on October 25, 2016, 03:03:40 AM
I used ATF for a long time then switched to 15 or 20 wt fork oil. Can't remember what I had last. I've been wanting to install gold valve emulators from Race Tech. Maybe over the off season as the fork seals have been leaking for some time.

paul
Title: Re: Racer Resurrection
Post by: bsracer on January 02, 2017, 12:17:40 PM
I thought I found the specs for the quantity somewhere on the internet. I think it was someone who specializes in Aermacchi's. 120 or 150cc per leg seems to ring a bell.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on January 18, 2017, 10:12:12 AM
Took a little time off for the holidays, but its back to schedule now.
(https://c1.staticflickr.com/1/688/32236139462_0415c24c22_z.jpg) (https://flic.kr/p/R7ADaY)

To revisit an old topic from post #63. The aluminum rims I got from eBay are no longer going to be used. Countless hours later, and they still refuse to become round and true.

So a set of Excel rims were ordered. I can not tell you how easy it was to build these rims. I had to send my hubs off to Buchanan Spokes for the rims to be drilled. The hole process took about two weeks from shipping them out to getting them back. Worth every penny.

(https://c1.staticflickr.com/1/538/32236140282_1dd39829ab_z.jpg) (https://flic.kr/p/R7ADq7)

And a video
(https://c1.staticflickr.com/1/403/32236140012_72dbcc2b3f_z.jpg) (https://flic.kr/p/R7ADks)

A new axle is being created this week. So the front end should be finished up by the end of the month. Then it’s on to the engine, and I suspect some work will be needed on the pipes.
Title: Re: Racer Resurrection
Post by: al_pritchard on March 23, 2017, 02:47:20 PM
I swear I’m making progress still. It’s just bit to cold to get out in the shop. So I’v occupied myself with internal engine bits.

I’m lucky that the bike came with 3 cranks. 2 in serviceable, if not usable condition. And the third is the one that wrapped the connecting rod around itself. Need to keep the other two usable until Paul perfects his new crankshaft process. ;-)

Crankshaft with spun connecting rod
(https://c1.staticflickr.com/3/2908/32767267824_7f6f2ce24d_z.jpg) (https://flic.kr/p/RVwP8w)

Backup Crankshafts
(https://c1.staticflickr.com/3/2924/33226604310_3993f622a6_z.jpg) (https://flic.kr/p/SC82S7)

I’m a bit curious about the center bearing between the two crankshafts.

The crank that was in the engine has the smooth center bearing. I have another one with the same bearing and one where the center bearing has a groove. Is there a fundamental difference? Or am I seeing the affect of an early and late part?


My wife splurged and bought me an aluminum removal tool for my birthday. Very excited! So I had to try it out and removed some aluminum. Lots of fun, and just a little scary. It helps that my wife is a jeweler, so as much as this is a new tool for me. She gets to use it as well. No matter, it was still fun removing a little metal.

New Toy!
(https://c1.staticflickr.com/4/3847/33226603690_5970581013_z.jpg) (https://flic.kr/p/SC82Fq)

Didn’t get to radical with my cutting. Followed the recommendations in the “Tuning Up for Competition” manual. Widening the exhaust port 2mm on each side, and widening the transfer ports 3mm. The transfers were a bit tricky, trying to keep the angle of the back of the port directing the flow. Guess we’ll see how I did eventually.

Aluminum!
(https://c1.staticflickr.com/4/3682/33226602900_9b2fd54367_z.jpg) (https://flic.kr/p/SC82rN)

Before & After
(https://c1.staticflickr.com/4/3695/33226599050_66339a40d4_k.jpg) (https://flic.kr/p/SC81iq)
(https://c1.staticflickr.com/4/3670/33226597930_e3b33ae706_k.jpg) (https://flic.kr/p/SC7ZY7)

The cylinders are off at Millennium now having the chrome “removed”. Then fitted for the new pistons and Nickel’d. They seem like a very good group and we took some time to talk about the bike and modifications. Correctly calling into question my sanity for turning a Bridgestone into a 200GP bike.

This weekend should see me CCing the heads in preparation for cutting them down. Lets just hope is warms up in the next couple of weeks to I can get back to the shop. Because I’m not sitting there in 34° to try to precisely skim off the head.

Burette
(https://c1.staticflickr.com/4/3792/32767395044_13b6482b6c_k.jpg) (https://flic.kr/p/RVxsWY)

After that its gathering gaskets, rebuilding the carburetors and sorting out an ignition.

For simplicity, I’ll follow the Dyna S points replacement guide. So that should be relatively uneventful.


Anyone have recommendations for carb rebuild kits, and gaskets? Does anyone have our pattern that provides different thickness cylinder base gaskets?
Title: Re: Racer Resurrection
Post by: OldSwartout on March 23, 2017, 08:41:21 PM
Re: center bearings - you're seeing early and late versions, the smooth one being the early version.  Diameters and width are the same.  Apparently, the early ones rotated in the bore, so they pinned them in later units.  That would be the best setup, but you'd have to machine the case for the locating pin. I suspect you could use Loctite Bearing Retainer on the early version and be OK if necessary, but pinning it would be more reliable.

I always wanted one of those angle grinders, but never bit the bullet.  Congratulations!

The Dyna S needs a third wire (+12V) to the trigger units that the points don't have, so you have to add it to the harness to the alternator/ignition unit.
Title: Re: Racer Resurrection
Post by: bsracer on March 24, 2017, 10:36:11 AM
Hi Al,

I'm assuming that what you mean by the smooth bearing you were referring to the one without the groove? As Karl was indicating one has a locating pin and one a groove. I thought the bearings with a grove and no locating pin are the early bearings. They get lubricated by the oil/gas mixture thru the hole in the transfer port and the mixture makes it's way around the groove. At least that's how I picture it. The later bearings which it looks like you have two, are located on a pin so that the hole in the transfer lines up with one of the holes in the bearing case. Maybe this was better for lubrication? I went back and looked at your earlier photos in the beginning of the post. It looks like you have an early set of cases as I don't see a locating pin in the upper half of the cases. I have had a good machinist add the hole to a set of cases. I also noticed that the RH profile pic shows the lack of a post for an idle gear and it looks like the oil port has been plugged to the upper left of the rotary valve cover. I've seen many different cases. I'll have to double check and see which ones in particular but some have no provision for the idle gear post, some have a plug that can be removed and you can add the post and the others have the post.

The difference being that the ones with no post are motors that the ignition spins at half speed. The motors with extra idle gear, the ignition spin at full speed. That is gonna make the difference on how you set up your ignition. If I remember the half speed ignitions fire at 90 deg and the full at 180 deg. The first ignition I set up only fired correctly on one cylinder because it wasn't triggering to fire the other cylinder at the right time.

As to where to get gaskets and stuff? I just got some base gaskets in aluminum from Cometic. I had base gaskets done there awhile ago (that I still have because I didn't like them) so I had them modify the file to be just a basic square on the outside with the 175 porting layout in the center. This way I can modify them to fit and I can trim them to fit a 200 case/port layout if I need. I got them in .025", .032" and .040". The 22mm carbs are pretty much the same as Kawasaki A1 250. I think there are kits available out there somewhere. I also had case cover gaskets done at Cometic so they should have the pattern. The part numbers for the aluminum base gaskets are B1055SP1025A, B1055SP1032A and B1055SP1040A. They cost me about $7-8 each.  I attached a copy of the base shim I use now. The Cometic ones are just square and need to be trimmed to fit.

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on March 24, 2017, 08:45:56 PM
My description of the bearings was confusing to say the least.  Paul's description is correct, the one with the groove is the early version, the one with the pin is the later.  I incorrectly called the one without the pin but with a groove the smooth one vs. one with a locating pin hole. Paul is also correct, the change to add the pin may have been to assure better alignment of the outer race with the lube feed hole in the crankcase; I had always assumed it was to keep the bearing race from spinning as many early Yamahas had that problem.

If you have a choice, it's better to use the crankcase/alternator combination that runs the alternator at full engine speed.  It's easier to set up points or convert to electronic ignition since it triggers at 180°.  You can put the 1/2 speed setup on a later crankcase by leaving out the idler and using the larger alternator gear, but you can't put the later one on the early crankcase since there's no place for the idler.

An interesting note on the carburetors - the A1 carburetors have the same slide, needle, needle jet and idle jet as the BS 175 racer carbs.  I always ran Mikunis, the A1 carbs were a real help since they have the enricheners, making cold starts much easier.
Title: Re: Racer Resurrection
Post by: bsracer on March 25, 2017, 03:08:47 AM
I looked at your picks again. It's funny to see the crazy stuff Bridgestone did. The early crank with the groove bearing has connecting rod bearings that have two rollers next to each other. These have bronze cages. Super trick. I'm sure they were too expensive and they went to a more standard type of bearing.  The earlier cranks also have center bearings with bronze cages. The later type are all steel. One of these days I'm gonna try one of the early bronze type center bearings.

paul
Title: Re: Racer Resurrection
Post by: bsracer on April 13, 2017, 02:57:51 AM
Hey Al.

Just a note to check the barrels when you install them to the cases. There is usually a fair amount of flashing from the process and the cylinders might be tight going into the case. You might have to file around the spigot until the cylinder fits smoothly into the case.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on April 26, 2017, 03:54:27 PM
Things continue to move in fits and starts. But I’ll take any progress at this point.

Cylinder Heads
Spent some time in the kitchen - or as I like to call it the mad scientist lab - the other week, playing with my new toy. It’s a 50ml burette and has plenty of capacity our little heads. Filled I can get 3 or 4 “test” fills into the head. A simple plexiglass plate, with a hole made up the rest of the lab equipment. Smeared with a little grease between the plate and head, and its off to races we go.

I took a cheep vice grip plier from harbor freight. Drilled a hole in the locking link, and bolted it to dial indicator holder and magnetic base. It made a good solid head stand, and allowed me to position the head with a slight angle upward toward the hole in the plexiglass plate.

For the CC-ing, I used an NGK B8HN plug. After all it’s the recommended plug in the manual, and filled burette with alcohol. I did 4 tests fills in each head. The average was 11.8cc. With the difference between each test being more my reading against the lines in the burette, or a slight over pour.

Custom Head Clamp
(https://c1.staticflickr.com/3/2873/33277611844_0910d8162d_k.jpg) (https://flic.kr/p/SGCsCm)

11.8 CCs of Alcohol
(https://c1.staticflickr.com/3/2935/33277612124_e231fc48ec_k.jpg) (https://flic.kr/p/SGCsHb)

The next task is to shave the heads to raise the compression. The manual recommends 1.5mm to 2mm or, 0.059” to 0.078”. To do that I’ll need to start by making up a jig to hold the head in the lathe. I’m thinking of a simple mild steal rod with the end turned down to fit up into between the fins and drilled to 14mm. Then use a 14mm bolt to “bolt” the head to the jig.

If anyone has any thoughts on a better way to do this..

On to the cylinders

The cylinders came back from Millennium, and boy do they look good. Perfect with a nice cross-hatch.

After a good initial chat when I sent the cylinders in, going back and forth between a piston clearance of .0020” or .0025”. We settled on .0020”. They also cleaned up the flat ends. One cylinder had a lot of markings on the deck from the aluminum gasket - over tightening perhaps?

(https://c1.staticflickr.com/3/2944/34078860306_a7b00cb1d0_z.jpg) (https://flic.kr/p/TVr4T1)

Started to check the ring gap. Could use a little guidance here, not sure where I should be netting out as far as how wide the gap should be. I read .015” or .381mm with nice steady resistance when I draw the feeler gauge out.

Ring Gap
(https://c1.staticflickr.com/3/2902/34078860526_b461419d83_k.jpg) (https://flic.kr/p/TVr4WN)

To Paul’s point above, some work needs to be done to the cylinders where they insert into the case. Both the smoothness of the port opening as well as the ports matching to the case. That should be the easy part.

(https://c1.staticflickr.com/3/2866/33446747114_7d823cc99a_k.jpg) (https://flic.kr/p/SXzjDG)

On the topic of running head gaskets. I'm debating running one, or getting the lapping compound out and attack the cylinder deck and head. A good flat lapped surface would allow me to run without a head gasket. It’s appealing but I don’t fully understand the drawbacks. One benefit is that it would effectively “raise” the cylinder ports in relation to the piston. And if I understand it correctly, provide better results in top end performance. Providing we get the compression ratio increased correctly. Then use the thickness of the base gasket to tune the final deck height and compression ratio.

A summary of Karl’s setup: He machined the head down .035", and did some machining to the chamber to net out at 7.2cc and with a compression ratio around 13:1. He is running with the stock head gasket.


(Edited to correct my description of how Karl machined his heads)
Title: Re: Racer Resurrection
Post by: vinny g on April 26, 2017, 05:02:12 PM
Hi Al.

I'd certainly do a dry build before machining the cylinders. You've happened upon a great way of increasing your port timings with very little work. The timings I run are around 134 degrees for transfer ports...and around 196 degrees for exhaust.Dry build and see what yours come out at...but you'll need quite a few more than standard if you want it to rev.

You can set the squish, such as it is with standard heads, by turning them so the combustion chamber sits inside the cylinder.
This is a good thing: It locates the head guaranteed centrally...it makes for a better seal.

We have a mandrel for skimming heads... basically a bar machined true with a 14mm sparkplug thread machined on the end.
Very often factories machined the heads this way so it usually runs true.Just mount the head and turn it down from the outside in until you're at ( if 175) 50mm etc.

Not the best description of things, I know, but it should make sense.

Title: Re: Racer Resurrection
Post by: OldSwartout on April 26, 2017, 05:55:37 PM
Al, there was a miscommunication, I took .035 off the top of the cylinders to take advantage of the automatic increase in port open time from the shorter piston.

Re: head machining; my brother has a commercial tool that is just a 1" round bar stock with a 14mm spark plug thread on one end like Vinny described. We used that to mount the heads in the lathe. It was inexpensive; I'll ask where he got it.

Edit: here's the link for the tool:
https://cometkartsales.com/M811-Misi-Head-Holder.html
Title: Re: Racer Resurrection
Post by: al_pritchard on April 27, 2017, 09:07:41 AM
Thanks for the correction Karl. I'v updated the post with .035".

Thats an interesting option Vinny. And a challenging one for my machining capabilities. But who doesn't like a challenge.
Title: Re: Racer Resurrection
Post by: bsracer on April 30, 2017, 03:23:28 AM
As Vince said about the dry build. Very important. I sent a set a cylinders back to Millennium for repair. These had already been plated by them previously. When I put the first cylinder on with my normal base shim, the piston hit the head. They apparently skimmed the cylinders on the base to square them up. I remember reading on their disclaimer something about that. Just didn't think it would be too much. I had to use the thickest base shims I had and some heads with a minor cut with about 8cc trap (with spark plug). Gotta go back and figure what base shim I will need since I usually run the piston 1mm down from the top of the cylinder.

I just had about four different sets of heads machined for dowel pins to locate the heads. I couldn't use any of them because the piston stuck out of the bore enough to hit and the thickest base shim didn't allow for enough clearance.

paul

Title: Re: Racer Resurrection
Post by: OldSwartout on April 30, 2017, 09:50:08 AM
Can you tell how much they took off? It sounds like it was a lot. That would affect port timing significantly.
Title: Re: Racer Resurrection
Post by: bsracer on April 30, 2017, 10:32:00 AM
I didn't measure them before I sent them so I'm not sure. These were also done by them once before. I measured them now and they appear to be around 80mm and a standard cylinder was around 82mm. When I pull it back apart to figure out what base shims I will need, I'll get an exact measurement. The thickest base shims I had were from Cometic and supposed to be .040". They measured out to .037" and the normal ones I use are .032". I was able to get a squish of around .87/.88mm so I went with that.


paul
Title: Re: Racer Resurrection
Post by: bsracer on April 30, 2017, 10:40:37 AM
First pic is of the heads I ended up using. It was these or some stock ones. The others didn't have any squish clearance.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on June 01, 2017, 09:51:45 AM
Did a dry engine build over the weekend, and took some measurements. Not sure I’m doing it exactly right, but here's to trying.

Cylinder Base to Deck: Left - 81.71mm and Right - 81.99mm
Cylinder Base Shim: 0.94 mm
Piston to Deck Height:   1.91 mm

Transfer port opens at 108° ATDC
Transfer port is fully open at 148° ATDC

Rear transfer port opens at 103° ATDC
Rear transfer ports is fully open at 178° ATDC

Exhaust port opens at 87° ATDC
Exhaust port is fully open at 154° ATDC

Rotary valve opens at 137° BTDC
Rotary valve is fully open at 100° BTDC
      
Rotary valve closes at a° ATDC
Rotary Valve is fully closed at 75° ATDC
* NOTE: Rotary timing is using the stock wiper. I’v not modified it yet.

Visual Timing
(https://c1.staticflickr.com/5/4226/34188213124_17f7a9eb36.jpg) (https://flic.kr/p/U66wEq)

I’m going to go back any do the measurements again to double check.

Vinny’s idea of stepping the head into the cylinder is interesting. Letting me run without a head gasket. But I don’t get the feeling that 1mm is enough.

I’d love to hear some thought on deck hight, squish and head cutting.
Title: Re: Racer Resurrection
Post by: bsracer on June 03, 2017, 11:07:40 AM
Hey Al,

I just sent some heads off on Thurs to a guy who does a bunch of Kawasaki H2 stuff. I still need to get him the piston crown angle and the deck height. He wanted to see how they might weld up. I'm interested if he can do something like I've seen done on Suzuki GT500. An insert like they do for water cooled bikes. You use a heat transfer paste between the machined parts.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on July 05, 2017, 01:48:42 PM
Hey Paul,

Very interested to see how that effort comes out. I’m having a hard time working out what direction to go with the heads.

On another note, who are you getting your tires from? I’m wondering if I’ll get lucky and be able to pick them up at NJMP weekend after next.

* Anyone else, feel free to chime in with a recommended tire dealer.

I’m thinking:
Heidenau K40R 2.50-18 Front
Heidenau K45R 2.75-18 Rear

Al
Title: Re: Racer Resurrection
Post by: OldSwartout on July 05, 2017, 06:19:07 PM
One of the AHRMA racers is a Heidenau dealer, so he'd probably be at NJMP, but unfortunately, I don't remember the name and he's not advertising on the AHRMA website.  He's probably in the AHRMA magazine, so you can probably check the ads there. 
Title: Re: Racer Resurrection
Post by: bsracer on July 07, 2017, 12:08:27 PM
Hey Al,

I just had some heads done. Not like the ones pictured. I'll post some pics when I can. I have been running the Heidenau's and they're ok. They change the gearing quite a bit from the Bridgestone BT39's.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on August 21, 2017, 10:53:16 AM

Keep me motivated Paul - Lets see some info on the heads.



Haven’t moved forward much, but I thought I’d check in and explain why.

If you’ve been following along, you may have noticed that the build had moved into my living room. Now I may have the worlds most understanding wife - but I will admit building a race bike in the living room is a bit of a challenge. So we began looking for a more “appropriate” location for my workshop. And we happened to stumble across a 1890’s farmhouse not far from where we live. With the best basement you could ask for. Fully dug out to 7' with a fresh painted slab floor. And did I mention someone built a bar down there. Long story short, we bought the house and moved last weekend. Still a lot to do to get the workshop us to speed. But it shouldn’t take to long.

At least she got to get out and see the sun
(https://farm5.staticflickr.com/4338/36667205786_7b85e33d36_z.jpg)

And arrived safe to her new home
[url=https://flic.kr/p/XSa1wj](https://farm5.staticflickr.com/4338/36667204806_ae5ab5d0db_z.jpg)

More updates as they happen. (https://flic.kr/p/XSa1Pd)
Title: Re: Racer Resurrection
Post by: bsracer on August 22, 2017, 11:25:52 AM
Very Cool Al.

Congrats on the new house. I like both the idea of bar and workshop down below. I have a friend who once lived in a house (in San Diego) that had a trap door in the living room floor that went down to a bar with pool table in the basement.

I've slowed up on things a bit too. The guy I was building the motor(s) for pulled the plug. I was still in mid production on a bunch of parts. One set of heads was for me one for him. The rotary valve covers aren't done yet and I still need to move forward of the ignition. This sets me back a bunch of $$$ so I'll just try and regroup next year. I will try out one set of the new heads at Barber in October. I hope to get them on in the next week or two and replace the ignition gear that failed.

The pics are of the two new sets of heads. First is 12:1 with a 10cc trap volume (I think?) and the second 14:1 with a 8.8cc volume. Both are set up for a zero deck height.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on September 25, 2017, 11:17:13 AM

The workshop is taking shape. New workbench built and moved the bike bench in. Also started putting in some new lighting. Cant recommend this lighting enough. 6 LED strips 4ft each. They put out a fare amount of light that is very white. It tends to feel brighter than it really is. I’m going to install  6 more in the back of the shop over the bike on a separate switch. Giving me one level of lighting for hanging out, and a second stage for working. Lights from Amazon (https://www.amazon.com/gp/product/B01HBT3BVM/ref=oh_aui_detailpage_o00_s02?ie=UTF8&psc=1)

(https://farm5.staticflickr.com/4413/36599612564_25287f9cdd_z.jpg) (https://flic.kr/p/XLbzGQ)

Bartenders View
(https://farm5.staticflickr.com/4441/36599612964_d061cb46ab_z.jpg) (https://flic.kr/p/XLbzPJ)

And View of the Bar
(https://farm5.staticflickr.com/4343/36599611884_ba9ed86448_z.jpg) (https://flic.kr/p/XLbzv7)



Paul. I’m interested in how you have the heads cut. It looks like you are setting them up for o-ring gaskets. I still weighing my options with how to cut the heads. And I’m not sure if ~1.5mm is deep enough to take the approach of cutting them to fit into the cylinder.

Did you cut the dreads to take an off the shelf o-ring? And if so, do you ming sharing the specifications?
Title: Re: Racer Resurrection
Post by: bsracer on September 26, 2017, 01:12:43 AM
Hey Al,

Workshop is looking good!

I sent them off to someone in the LA area. I don't have any of the specs. I guess I can get them if he'll give them to me. I think he uses some software because I had to provide him with a bunch of different measurements. He had to build up both sets of heads with weld. The 10.0 heads have quite a bit more compared to the 8.8cc heads.

The orings are off the shelf. YZ125/85. I can send you the part number when I get a chance.

I just put the motor together Saturday and into the bike yesterday. Sounds/feels pretty good. Gotta get my stuff together and up to LA on Friday to get everything to Barber!

paul
Title: Re: Racer Resurrection
Post by: SR-175 on October 23, 2017, 11:05:11 AM
Hi Karl,

Would you mind sending me this file in the three formats you can ? Not sure yet what the printer wants just yet.

Thanks .. ray - ray@bsrestoration.com

From Karl :
Here's a similar size logo in .jpg.  I also have it as a vector file in .wmf, .dxf and .dwg line formats that can be easily scaled and/or used to cut decals or stencils.
Title: Re: Racer Resurrection
Post by: OldSwartout on October 24, 2017, 08:53:29 AM
Files sent to your email.  They can't be attached to post due to the file formats.
Title: Re: Racer Resurrection
Post by: SR-175 on October 24, 2017, 10:54:02 AM
Hi Karl,

Got them and thanks !!... A bit of tweaking to do but getting there.
Title: Re: Racer Resurrection
Post by: SR-175 on October 24, 2017, 10:56:05 AM
Oops ...
Title: Re: Racer Resurrection
Post by: al_pritchard on October 24, 2017, 12:18:50 PM
Hey Paul, how'd you do at Barber? It looked like the 200Gp grid was rather large this year.


Been sniffing around the Yamaha 2-Stroke forums looking at how they are doing o-ring head conversions. And I'm gaining confidence that I can pull this off. The groove does not not to hard to machine. And since I'll have the head on a lathe anyway, might as well cut a groove.

It looks like lot of the Yamaha guys are using off the shelf high silicon o-rings from McMasterCarr. $7.00 for a packet of 10. And that may be an alternative to the Yamaha o-ring.

I think my measurements are close - I'm beginning to questions the accuracy of my tools and technique. But this is what I came up with:

There are 3 potential o-rings that would work with the material space we have available on the head.

Dash Number 037, 036 & 035 o-rings. The 036 o-ring would sit almost dead center between the bore and the stud hole. With 0.417 / 0.402 on each side (actually a little less as the groove needs to be slightly wider that the o-ring)

(Edited, because I suck at math)
The Dash 035 o-ring is probably the best bet. Re did the measurements last night and realized I didn't account for two things. One, the cylinder head surface is narrower at the side, than it is at the stud holes. And I was effectively doubling my measurements.


Curious abou the Yamaha part number Paul, and the groove dimensions from your heads. I suspect Yamaha uses a standard dash number o-ring. Looking at the head images above, I suspect it's the 035 size. As the groove looks to be centered between the bore and the stud holes.
Title: Re: Racer Resurrection
Post by: bsracer on October 26, 2017, 11:19:41 AM
Hey Al.

My bike ran well at Barber, I didn't. I seem to have fallen into a habit of backing off when I shouldn't. I'd turned a 2:04/2:05 at Barber in the past. The best I could pull off was a 2:08. The fast guys in GP200 were in the 1:57's. The group of people I think I can hang with were in the 2:01 range.  I'm gonna switch back to the Bridgestone tires for next year. Maybe it's a mental thing but I can't seem to go faster than I use to. I've had the Heidenau's on for a few seasons. I can't ever seem to gear it right. They are quite a bit taller than the Bridgestone BT39SS.

paul

I can give you the guys ph# who did the heads. I don't have any info on what he did only the trap cc volume. I ran the 8.8cc heads at Barber. I want to dyno the bike before I take it apart to look at everything.
Title: Re: Racer Resurrection
Post by: hardy on October 27, 2017, 05:15:52 AM
YOu Should be able to download the boring groove specs from any good manufacturer ie Parker or ludiwinci

Hardy.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 27, 2017, 09:23:42 AM

Marko has a relatively easy to read chart that I'v been referencing. (https://www.marcorubber.com/o-ring-groove-design-face-seal.htm).

I'v been looking for a Parker chart, but I think you need to buy the book. I'm going to risk it, and use the Marko measurements. I suspect I won't be as exact as a real machinist ... so the accuracy to the 100th may be lost on me.  :o

Title: Re: Racer Resurrection
Post by: al_pritchard on November 26, 2017, 06:56:48 PM
Happy Thanks Giving Everyone!

So finlay, forward progress. Spent some time Saturday on the lathe - I'm still learning but I'm getting better.

I took 0.059in (1.5mm) off the head, and cut the o-ring grove. Making the tool to cut the grove took the most time, but I think I managed to do a fairly good job. The new measurements are:

O-ring Gland
Width: 0.084in
Height: 0.052in
Outer Diameter: 2.379in

Deck Hight: 0.060in (1.54mm) *With medium base shim
Base Shim: 0.0315in (0.79mm)
Spark Plug: B-8HN
Head Volume 8.3cc

Still need to cc the cylinder to work out total volume. At some point this winter when I don't want to go out in the snow, I'll tackle that. Until then, I tink I might be okay with - the removal of the head gasket, and going with the o-ring should help off set the lower hight of the RM piston. And swapping between the the thick, medium, and thin base shim should allow me a little flexibility between compression ratio and port height.

(https://farm5.staticflickr.com/4515/38633502452_072edcaea1_k.jpg) (https://flic.kr/p/21RUNiS)

(https://farm5.staticflickr.com/4569/38633506712_212021f508_k.jpg) (https://flic.kr/p/21RUPzj)

I do wonder if the o-rings I have are the same dimension as the ones Paul is running. They look similar form the photos.
Title: Re: Racer Resurrection
Post by: al_pritchard on January 01, 2018, 09:09:01 AM
Happy New Year Everyone!

Finished up 2017 with an arts and crafts project, and final preparations for the engine build. First, arts and crafts!

Over on the North American Two-Stroke forum (natsforum.net) there is a thread about someone rebuilding/freshening his '97 TZ250 for 2018 vintage racing. One of the tasks was the creation of an "air dam". It go me thinking. I had a large area un-covered by the fairing, just under the tachometer. The fairing has a plate that normally covers this area, but it's designed to be use with the stock steering yoke. The upgraded yokes that I'm using are thicker and stick down lower that stock. I couldn't work out a way to get the fairing mounted low enough to use that plate.

The air dam might just do the trick: lowering the debris entering the cockpit, and funneling more air to the engine. Started with a simple cardboard mockup. Transferred to "marine board" available at West Marine, it's the same as HDPE plastic sheeting. Cool stuff, cuts just like wood, but you can't glue it.

You can see the space between the forks, that would normally be covered
(https://farm5.staticflickr.com/4734/38549722455_acdc4f84a2_z.jpg) (https://flic.kr/p/21Jvpra)

Cardboard!
(https://farm5.staticflickr.com/4645/38720131574_836c63f944_z.jpg) (https://flic.kr/p/21ZyN8q)

(https://farm5.staticflickr.com/4639/38720130614_8373e4dcfb_z.jpg) (https://flic.kr/p/21ZyMQS)

Plastic!
(https://farm5.staticflickr.com/4637/38720129864_1bc2d52f2f_z.jpg) (https://flic.kr/p/21ZyMBW)

(https://farm5.staticflickr.com/4594/38720128654_09b36d19a8_z.jpg) (https://flic.kr/p/21ZyMg5)


Engine Build
All the parts have been striped down, cleaned, oiled, and prepared for assembly. Only one thing missing, gaskets. :o I was originally planning on not using a gasket, and relying on Yamabond. But when I did a final test assembly, and tightened down the case bolts. The crank felt like it was binding, and I had a very hard time getting the transmission to shift. Everything is very smooth before tightening everything up. So I guess gaskets are a necessity.

Paul, Karl what are you doing for gaskets? Cutting your own or buying?

All prepared for assembly
(https://farm5.staticflickr.com/4641/38720135534_f642cc0087_z.jpg)

[url=https://flic.kr/p/21ZyNmG](https://farm5.staticflickr.com/4684/38720132344_13c48da75e_z.jpg)

[url=https://flic.kr/p/21ZyNBb](https://farm5.staticflickr.com/4680/38720133184_fdba166e58_k.jpg) (https://flic.kr/p/21ZyPiG)
Title: Re: Racer Resurrection
Post by: OldSwartout on January 01, 2018, 10:43:28 AM
I cut my own cylinder base and clutch cover gaskets, both to save money and to use better gasket material. From my job, I knew about gasket materials with release agent on the surface, so there weren't worries about stuck gasket material when trying to change parts in the pits. I scanned originals and then printed patterns as needed, stuck the printed pattern to the gasket material with a glue stick, cut with an Exacto knife; a bit tedious. That way I always had plenty of spares.

There isn't a gasket between the crankcase halves, only sealer.  If things don't spin freely when the two halves are tightened, there is an issue that needs to be addressed. Transmissions are somewhat difficult to shift unless pretty well oiled, but the individual shafts and the shift drum shouldn't have any noticeable drag when spun.

The air deflector you designed for the fork/lower triple is a really good idea.
Title: Re: Racer Resurrection
Post by: al_pritchard on January 01, 2018, 12:11:12 PM
Thanks Karl. It was the difficult shifting that had me worried - as it's very smooth with the cases split. I'll seal it up again and double check.

On another note - it's not all bad that I had this pause moment. In re-checking everything I find that I am in possession of a pre November 1965 shift drum (pre serial no 16W02913). This gives me a shift pattern of 1N234N5. The post November shift drums give a more favorable - for racing - N12345.

Does anyone know if it's a direct swap between the old and "new" drums? And does anyone have one for sale?
Title: Re: Racer Resurrection
Post by: bsracer on January 02, 2018, 03:07:35 AM
Yamaha bond or something similar is the only thing to seal between the case halves. Don't use RTV.  Your crank set up looks like there is no locating dowel in the cases. Is there a circlip retainer against the seal as well? Shift fork B (#12) in the parts diagram is different from the ones in a SR175. Unless you are going to lock out the rotary shift somehow, that little spring and plunger is omitted and the shift fork for a racer just takes the same pin and roller as the other shift forks. When you assemble the bottom end you have to install the clutch bearing retainer before you tighten down on the cases (the trans can move over and be out of position if the cases are tightened first). You also have to make sure the crank is not binding on the cases. Put it in the top half and spin it then put it in the bottom half and spin it. Then put it in the cases and with just a few case bolts just snug them up a bit and keep checking how the crank turns over.

I have never put a motor together that doesn't have the locating dowel and circlip for the crank. Maybe the crank is a bit out of position. It doesn't take much. When a crank is not pressed back to all the way the webs can rub on the cases.

In looking back at your post, the early shift drums that have the different pattern also have a few different gears on the cluster. The drums can not just be swapped. The early drum should have what looks like two neutral indents. The later ones only one. I probably have a good stock setup. I also have an under cut set that would be preferable and some refurbished shift forks (including the SR style #12 fork). I'll take a look tomorrow.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on January 02, 2018, 07:47:25 PM


Yep, no locator pin. But there is a circlip retainer that holds against the seal. I guess they made a number of updates towards the end of '65.

Thanks for the tip with the clutch bearing retainer may answer why I was feeling a little resistance.

I have the rotary shift fixed in place with a simple bracket. I must confess this was put on by the previous owner, so I cant take credit for the welds. But I do wonder if this transmission is what lead to the spun crank? Ful chat down the straight at 10k plus RPMs, and shifting from 4th to neutral may have allowed him to over rev slightly. ¯\_(?)_/¯

Rotary Shift Lockout
(https://farm5.staticflickr.com/4636/39461295221_b4af8084d8_z.jpg) (https://flic.kr/p/2384sfZ)

Shift Drum with Spring & Plunger
(https://farm5.staticflickr.com/4638/38752720264_0f51533fbe_k.jpg) (https://flic.kr/p/223rPBo)

I would be verry interested in ether of those transmission options. Don't think the current configuration is going to cut it.
Title: Re: Racer Resurrection
Post by: al_pritchard on January 08, 2018, 08:48:52 AM
With the final assembly of the engin on a short pause while I source an different transmission. I thought Id move on to the controls. I get a little rubbing of the clutch cable under the tachometer. My hope was to run the clutch through the air-dam. But that causes some slight movement of the clutch lever then fully turned right. I'm going to re-make all the cable controls, as the new levers have a longer distance between cable end and the casing. I'm hoping that better matching the cable and casing length may allow me to run through the air-dam.

(https://farm5.staticflickr.com/4737/24708568267_690f774189_z.jpg) (https://flic.kr/p/DDpSvH)

(https://farm5.staticflickr.com/4589/38680044375_28665c6140_z.jpg) (https://flic.kr/p/21W2kAP)

Still have some tweaking to do to the foot lever. Would like to get the angles to match between the shift lever, and the foot level. And boy do I hate threading stanless steel.

(https://farm5.staticflickr.com/4595/27799788509_4fc298253b_z.jpg) (https://flic.kr/p/JmzbAr)
Title: Re: Racer Resurrection
Post by: old smokey on January 08, 2018, 06:05:51 PM
I feel like I'm going to an art exhibit looking at the photos!  8)
Title: Re: Racer Resurrection
Post by: al_pritchard on January 16, 2018, 07:30:28 PM
Weekend Update!

This weekend was all about cables. Throttle and clutch - brake cable should happen next weekend.

Throttle cables were rather simple. Bought two universal throttle kits from Venhill, and assembly was pretty easy. Although I couldn't find an end fitting exactly like ours. I did fing a "Trumpet Nipple" that could be made to work.

A 1" copper end makes a simple crucible to melt the solder.
(https://farm5.staticflickr.com/4767/39702019462_cdcb6a7d72_z.jpg) (https://flic.kr/p/23ukebW)

Nice little birds nest
(https://farm5.staticflickr.com/4717/38835018665_94f5bc4779_z.jpg) (https://flic.kr/p/22aHC4k)

Quick dunk in the solder, and a little filing
(https://farm5.staticflickr.com/4663/39733432291_ba50f425b3_z.jpg) (https://flic.kr/p/23x7e8r)

I took the throttle cables out a little far to help avoid any interference when turning.
(https://farm5.staticflickr.com/4702/39022269884_19da0ee51b_z.jpg) (https://flic.kr/p/22sgkjC)

Would love some thoughts on how to run the clutch cable. Again going to run long to prevent any interference when turning. But the cable always seems to end up under the throttle. Perhaps a loos zip-tie to the fork leg?



And Paul. I still owe you a phone call. Got a little distracted this weekend.
Title: Re: Racer Resurrection
Post by: bsracer on January 17, 2018, 11:28:45 AM
Hi Al.

I need to make some new throttle cables for my current set up (22mm)  and for some 24mm carbs I want to try. Here's some pics of how I run the cables. I usually have a zip tie loose on the clutch, throttle and front brake. I use a throttle off a YZ85 or RM85 to a splitter under the tank. I put some aircraft cable/wire hangers on the frame with big enough loops to let the cables move if they need to.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on February 14, 2018, 02:56:43 PM
Hey Paul,

That looks clean and tidy.

I was a little worried about making the cables. Turns out to not be to hard. I'll look into aircraft cable hangers, might be a good idea.
Title: Re: Racer Resurrection
Post by: al_pritchard on February 14, 2018, 02:59:04 PM
Waves of good and not so good progress. The transmission situation is now solved - I still owe you a call Paul but  had to take a cheeper option for a little while.

I managed to find a RS200 transmission with both shafts, drum, and dogs. I was esthetic, everything I needed at a very good price. When the transmission arrived everything looked good. So I started to tare it appart for a good cleaning and oiling. This is where I encountered my first problem. It seems someone had sheered one of the shift pins in the drum. What was worse is it looked like they had jammed the broken pin back into it's hole. Luckily, I was able to walk it out with a pair of mettle sheers. So no harm done.

But the next part was much worse. I had to use a bearing puller to take the small bearing off the countershaft. Unlike the shaft of my 175, where the bearing just slides on and off with ease. Once I got the bearing off the reason for its tight fit was apparent. Someone had been grinding on the end of the shaft!

A week later and I had another countershaft - this one was perfect! So the transmission, and crankshaft are installed, along with pistons. And this time I installed the bearing plate. Everything spins smoothly and shifts as it should - N 1 2 3 4 5.

Also a little cutting and filing was completed on the cases. Making it a little easier to access the carbs, and trimming a little weight. This does leave me in need of a right side carb cover. Don't need one in good shape. The plan is to cut most of it off, and just use the clutch adjustment cover part. And I don't want to cut up the racer covers I have. So if you have one, Im interested.

Ignition is next! Stay tuned.

Driveshaft RS200 on top DT175 on the bottom
(https://farm5.staticflickr.com/4611/38458238830_8a8a0bddc7_z.jpg) (https://flic.kr/p/21Aqwxh)

5th Gear RS200 on top DT175 on the bottom. Note that this is the early pre November '65 DT175 gear
(https://farm5.staticflickr.com/4603/38458238420_a5ec11b1c2_z.jpg) (https://flic.kr/p/21Aqwqd)

DT175 countershaft with RS200 driveshaft. Note that the 175 outer gear (5th) sits wide on the 5th countershaft gear. Makes a hell of a racket when you spin the transmission.
(https://farm5.staticflickr.com/4714/38458237050_f27dfe4c04_z.jpg) (https://flic.kr/p/21Aqw1A)

The RS200 transmission. Note the 5th gear on both shafts. The driveshaft geer is narrower and more inset than the one on the DT175
(https://farm5.staticflickr.com/4667/40223808842_74e21f9752_z.jpg) (https://flic.kr/p/24hrwZy)

Trimmed up clutch cover
(https://farm5.staticflickr.com/4622/40223807002_0d1f4d1cbf_z.jpg) (https://flic.kr/p/24hrwrQ)

(https://farm5.staticflickr.com/4623/40223807392_dd338e5c98_z.jpg) (https://flic.kr/p/24hrwyy)

Bad RS200 countershaft. Click through to zoom in.
(https://farm5.staticflickr.com/4655/40223810532_ecf1678841_z.jpg) (https://flic.kr/p/24hrxuG)


The offending shift pin. Note the part still in the drum.
(https://farm5.staticflickr.com/4766/40223809192_53bcdb3327_z.jpg) (https://flic.kr/p/24hrx6A)
Title: Re: Racer Resurrection
Post by: al_pritchard on February 21, 2018, 01:54:17 PM
Final dry engine assembly underway, and the ignitions is built.

I'v an older engin case, that has an ignition that spins at half speed. And that means I need to use the Dyna S DS1-3. It's configured with the pickups at 90°, and 2 magnets at 180°. The half speed means that we need to trigger the pickups 4 times for every rotation. Being a visual person, I didn't understand it until I assembled it. Then it was cristal clear.

The first step was to turn down the old cam at the end of the generator shaft. Rather than remove the cam from the generator shaft. I removed the shaft from the housing and treated it like a mandrel in the lathe. If you have a generator with "guts" you wont be able to do that - luckily mine doesn't.


Out with the old, and in with the new
(https://farm5.staticflickr.com/4715/38592522870_c6e8f647b7_z.jpg) (https://flic.kr/p/21NhLvm)

Generator and points cam
(https://farm5.staticflickr.com/4675/38592525420_4cb812fbae_z.jpg) (https://flic.kr/p/21NhMgj)

(https://farm5.staticflickr.com/4610/39506712055_d6f0e1966a_z.jpg) (https://flic.kr/p/23c5e6R)

Fitted
(https://farm5.staticflickr.com/4710/26532493608_f3ca159607_z.jpg) (https://flic.kr/p/GqzXYm)

Installed
(https://farm5.staticflickr.com/4655/26532482048_bef1805677_z.jpg) (https://flic.kr/p/GqzUx3)

Still need to make a wiring harness and test this. But I'm ever hopefull.
Title: Re: Racer Resurrection
Post by: OldSwartout on February 21, 2018, 09:11:42 PM
Nice work!
Title: Re: Racer Resurrection
Post by: al_pritchard on March 07, 2018, 03:49:04 AM
Thanks Karl. Now lets hope it works.  ;D
Title: Re: Racer Resurrection
Post by: al_pritchard on March 31, 2018, 06:56:05 PM
Less of an update on the build, and more of a post for guidance. I'm looking at you Karl, Paul, Jack, others.... The topics for today are electronics and exhaust. Lets start with electronics.

I'm planning on running a relay between the battery and the coils. My question is, should I run two relays with separate feeds to each coil off the positiv terminal? Or is one relay branching to each coil sufficient.

Could also use some guidance on my tachometer. I'm at a loss to find anything on google regarding how to wire it up. It's a 0 to 14,000k Daytona. With a Black, Yellow, Red, and White wire. It currently has the black and yellow wire soldered together. Leading me to believe they are ground? If anyone has any thoughts as I'v never wired up a tachometer. So flying a little blind.

Daytona Tach
(https://farm1.staticflickr.com/895/26273235297_833e970d1f_z.jpg) (https://flic.kr/p/G2Fcvt)

My other question is about the exhaust. Opened it up today to look at repacking it. And its empty. Would have thought I'd find some holes in the end of the stinger with some wadding. Is everyone just running a stinger, with a pretend baffle? Or do I need to brake out the drill? And if so, what should I use as baffle material?

(https://farm1.staticflickr.com/822/26273235737_f4947df0e1_z.jpg) (https://flic.kr/p/G2FcD4)
Title: Re: Racer Resurrection
Post by: OldSwartout on March 31, 2018, 09:03:53 PM
For the silencers to work, there has to be many holes drilled through and it would have to be packed with fiberglass.  You can buy fiberglass packing kits for silencers from many motorcycle suppliers or just use normal building insulation fiberglass.  As is, there is no silencing.  You probably won't be able to run in any sanctioned races that way, nor would you want to.
Title: Re: Racer Resurrection
Post by: al_pritchard on April 02, 2018, 11:41:36 AM
Yea, running with no silencer would not be a good idea. I guess thats part of taking over someone eases project. You never know what you are going to find.

Spent a couple hours on the drill press yesterday. Wont be winning any awards from the profesional fabricators, but once it's packed and sealed no one should be able to tell. I do wonder if it will be enough, so this may change to become an aftermarket silencer in the future. But to get the bike started, and let the neighbors know it runs this should work.


(https://farm1.staticflickr.com/803/40473487554_b12ab3f7b6_z.jpg) (https://flic.kr/p/24EvcLW)

(https://farm1.staticflickr.com/872/40473487794_18cb02a8b3_z.jpg) (https://flic.kr/p/24EvcR5)
Title: Re: Racer Resurrection
Post by: bsracer on April 07, 2018, 11:25:07 AM
I like that someone had fake silencers! I use to run the same tach. After a crash the needle stuck and I now run a Scitsu. I don't remember (meaning I can't find it) where I put the Daytona tach but I might have the orig paperwork on how to hook it up. I got it from K&L supply and it's from Shindy products. I'll look for the paperwork. I seem to remember there are some switches under a little plug in the back for firing.

Those holes look pretty good for the stinger! I have some Jolly Moto silencers from a RG500 that were shortened only because the bike was crashed and we salvaged them. I was getting a 98db reading at Barber so well within ok sound levels. Yours look pretty short but they should be quieter than the straight stingers.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on April 09, 2018, 09:59:22 AM

Yep, thats the tach. I'm hoping that the switches are set correctly, since it came with the bike. But if you happen to find the instructions I would be verry grateful.

(https://farm1.staticflickr.com/895/26273235297_833e970d1f_z.jpg) (https://flic.kr/p/G2Fcvt)
 
The silencers are rather short, and I expect that they will not quiet the bike enough. But they will keep me moving forward for now. I'll keep an eye out for something to use in the future.

That big square of material compress down into that little cylinder.
(https://farm1.staticflickr.com/877/26470074307_4fbf79c849_z.jpg) (https://flic.kr/p/Gk53Tv)

Completed the final - I hope - dry build yesterday. I need to go back and re-read the assembly, and parts manual. When spinning the engine there is a slight amount of resistance every now and again. I don't think it's related to the crank, or pistones. As that assemble spins smoothly without the clutch basket mounted. My thought is ether the clutch, crank gear, or generator gear are not aligned proporly. Or one needs to be shimmed.

I also noticed just a slight looseness of the clutch basket and back plate gear. Should I expect this, or do I need to start looking for a new basket?

(https://farm1.staticflickr.com/794/26470072567_8287816744_z.jpg) (https://flic.kr/p/Gk53nv)

(https://farm1.staticflickr.com/808/26470070767_9b0d460c8c_z.jpg) (https://flic.kr/p/Gk52Qt)
Title: Re: Racer Resurrection
Post by: bsracer on April 09, 2018, 10:37:22 AM
I found the wiring diagram. Hope it helps. The clutch gear has rubbers in between where it's riveted together. They can be a bit loose sometimes. Mine seems very loose at the moment so I will double check it. Are you going to paint it blue and white? The guy who made the Bridgestone Katana decals is Ed Morgan in Maryland 301.865.5599.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on April 09, 2018, 11:13:39 AM
Okay, I wont worry about the movement then. One less part to buy/fix.

Thanks for digging that up. Will be super helpfull.

I was originally thinking blue and white, like the old factory bikes. But the Leopard Moto3 and NYC Norton blue have me thinking. Not settled yet, but if you have ideas.

Thanks for Eds number. I'll give him a ring as soon as I work out the livery.
Title: Re: Racer Resurrection
Post by: al_pritchard on April 15, 2018, 01:27:58 PM
Lets talk batteries

The last big thing to work out is power, and wiring. Would love to here what everyone else is running.

Can a SpeedCall 2.5 Ah (https://shopspeedcell.com/products/legacy-2-5ah-supersport-battery-with-universal-ring-terminal-harness) battery last a race with a comfortable margen? Or should I be looking at a bigger battery?

Was planning a simple wiring harness. Isolating the battery with a fuse (I think I'll need a 30, and not a 15), and a relay. The Dyna S came with a ballest resistor. But I think that would only be needed in the circuit if a generator or alternator were used. Am I right on that?

(https://farm1.staticflickr.com/865/26605066797_f2df9671e9_z.jpg) (https://flic.kr/p/GwZVse)
Title: Re: Racer Resurrection
Post by: OldSwartout on April 15, 2018, 06:12:26 PM
I'd be somewhat nervous with a 2.5 Ah battery, although it should last one race.  i used to run a standard 14 Ah  battery. It would run a full weekend - 4-5 practice sessions + 2 races, but that was about it.   
Title: Re: Racer Resurrection
Post by: craig641 on April 21, 2018, 05:29:56 PM
I used, through last season, a 4ah battery.  There were too many races that I dnf'd because of a dead battery.  I realized that the few ounces I saved wasn't worth it if you don't finish.
Title: Re: Racer Resurrection
Post by: OldSwartout on April 22, 2018, 09:26:30 AM
It seems to me that one of the Lithium-Ion automotive jump start batteries rated at 20,000 mah should work and they weigh less than a small lead acid battery.  They are less than $100 at Walmart, etc.  The issue would be vibration, I think.  They probably aren't designed for a high vibration environment. 
Title: Re: Racer Resurrection
Post by: al_pritchard on April 27, 2018, 08:18:17 PM
This is what happens when I start over thinking things.

Taking a gamble on the battery. Two coils, rev counter, and transponder shouldn't flatten the battery in race time. Calculations vs. reality...

Standard place to mount the battery would be under the seat/tank. But I started thinking, what if I mount them on the air dam on the forks? It's a super light set up, and moving them forward would keep them away from the heat. Would need to change the material the dam is made of. I did a quick mock up with a fome core and fiberglass. Feels stiff, and can always build for USCRA, and use carbon fiber.

What do you think? Am I mad? To risky?

(https://farm1.staticflickr.com/903/41747556551_60d75d82db_z.jpg) (https://flic.kr/p/26B696M)

(https://farm1.staticflickr.com/960/41747556241_6dea4a2690_z.jpg) (https://flic.kr/p/26B691r)

(https://farm1.staticflickr.com/903/41747555851_1ed960a309_z.jpg) (https://flic.kr/p/26B68TH)

(https://farm1.staticflickr.com/966/41747555531_d92db75d70_z.jpg) (https://flic.kr/p/26B68Nc)
Title: Re: Racer Resurrection
Post by: hardy on April 27, 2018, 08:55:28 PM
I like the idea and your thinking, but in real terms my thoughts would be from time to time race bikes do have unfortunate accidents, so perhaps a more protected location were be better?

P.S, I have really been enjoying following this thread! Keep up the good work! banana

Hardy.
Title: Re: Racer Resurrection
Post by: OldSwartout on April 28, 2018, 08:16:47 AM
I'm with Hardy, it's probably more vulnerable there, although a solid hit directly in front of the forks isn't as likely as side damage from sliding.  It is more isolated from engine vibration and heat there instead of mounted directly to the frame under the seat/tank and the access might be better.   Nice setup either way.
Title: Re: Racer Resurrection
Post by: BRT-GTR on April 28, 2018, 09:43:16 AM
             I have no experience of automotive Lithium-ion batteries but have used them extensively for model aircraft flying.    Misused they can be dangerous  ------   ask Boeing about cockpit fires!!

         They must not be overcharged - can go on fire and cannot be extinguished, contain their own oxygen supply. 
       They must not be discharged below a set voltage (forget the figure) , that kills them.

       I assume automotive Li batteries have  built in electronics to prevent over charging/discharging..

   The ones I used came with dedicated chargers that cut off at the max voltage.  The onboard electronics would also shut off or go to low rate at a set discharge voltage.

       Used sensibly and fully aware of their characteristics, they are fine and have a great perfomance/weight ratio.      Make sure the intructions are understood and don't use normal lead acid chargers, unless instructions say you can.   I've seen many expensive model aircraft burned to a pile of ash because users didn't follow the instructions.
           Hope I haven't put you off,  bikes coming on nicely,    Brian.
Title: Re: Racer Resurrection
Post by: bsracer on May 01, 2018, 10:57:28 AM
My friend uses a Dewalt 14.4 drill battery. Not the lightest but easy to change out and will power all the tools we bring (drill and impact gun)! He typically has them charged and when he comes in he swaps new one every time. The newer batteries are much lighter. Might be tricky to adapt to still use the orig charger.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on May 01, 2018, 02:34:29 PM
Hey Brian,

Yea, they can be a bit tricky - and flammable. But with a good charger, and charging protocols it should be safe. It's a LiFePO4 battery, slightly safer but still susceptible to fire.

So I'm going to try the airdam mount. But I also created a mounting plate for under tank, just in case....  ^-^

About the battery selection. I think I got the calculations close??? Otherwise I'll be looking for a deferent solution. But that's part of the fun, isn't it...  :o

With the Dyna S ignition and a 4.6 ohm stock coil we should get something in the 2 to 3 amp draw. With one coil reaching saturation when the other fires. The trick / hope is that the coil reaches saturation just before it fires. So we don't continue to pump energy into a fully saturated coil.

Interesting idea with the Dewalt battery Paul. And makes me think I may be ok with my selection. The older 14.4v ones were only 2.4 Amp.
Title: Re: Racer Resurrection
Post by: al_pritchard on May 14, 2018, 04:15:15 PM
Wiring harness weekend!

Not sure I completely understand how the wiring works - Dyna S, and the Coils. So if you spot something that looks off, please let me know.

Dyna S gets fed power on the RED wires (x2) to the positive post from the battery. The black and white wire from the the Dyna S, connect to the black and white wire on the coil. The blue wire on the coil connects to the positive post from the battery. In essence, two separate circuits. The Dyna S grounding through one side of the coil to the chassi. The coil grounding through the spark plug.

So it's ok to have the power side of the coil, and the power side of the Dyna S on the same pole from the battery?

The connectors are "Deans" connectors. If you ever raced RC cars, you probably encountered them.

Power comes off the battery into the "hot" side of the bus bar. The Coil, Dyna S, transponder, and tac all connect to the hot side. The ground/neutral bolts to the chassi. Then the ground side of the bus bar bolts to the chassi - safety wire will hold the bolts in place.

The tac will ground to the bus bar as well - need to tie that in yet. The white wire from the tac connects to the white wire on the coil.


(https://farm1.staticflickr.com/827/42112573671_bba4e13960_z.jpg) (https://flic.kr/p/27akWYp)

(https://farm1.staticflickr.com/904/42112574251_5faff278d2_z.jpg) (https://flic.kr/p/27akX9p)

(https://farm1.staticflickr.com/952/42112577091_635e5ddf52_z.jpg) (https://flic.kr/p/27akXZn)
Title: Re: Racer Resurrection
Post by: al_pritchard on May 18, 2018, 10:15:54 AM
Arts and crafts night! Or as I like to call it - Fun With Cardboard.

They dont seem to be required yet - but I seem to remember seeing that they are sugested. And it's probably a good idea.

I'm a little leary about drilling into the swingarm tube. But I think I should be ok drilling into the flat axle flange. Couple of cardboard mockups to get the shape right. Then on to aluminium. Add lightness, and .... still need to dril out the flange to mount it.

(https://farm1.staticflickr.com/824/42190760131_730dc5512d_z.jpg) (https://flic.kr/p/27hfF5P)

(https://farm1.staticflickr.com/973/42190759991_f35b634dce_z.jpg) (https://flic.kr/p/27hfF3p)

(https://farm1.staticflickr.com/903/42143460792_91f8561eeb_z.jpg) (https://flic.kr/p/27d5fCY)
Title: Re: Racer Resurrection
Post by: bsracer on May 22, 2018, 10:04:18 AM
Looks good. Might not be mandatory before brake guard levers will be. You will need to cover the chain adjuster bolts that stick out. Just use a  short piece of fuel hose.

paul 
Title: Re: Racer Resurrection
Post by: al_pritchard on May 29, 2018, 10:05:38 AM
Yea, the adjuster bolts are already drilled for safety wire. But I think your suggestion i better. Assuming I'll be doing a fare amount of adjustment as the chain brakes in. And I work out the proper bike setup.

Thinking about brake guards as well. Found one that I think will work out of Germany, from RaceFoxx.com. I could only find a handfull that clamp around the bar. It has the added bonus of being 3D printed, so thats cool.

RaceFoxx Brake Guard - Ended up moving it out slightly on the bar to prevent interference with the lever.
(https://farm2.staticflickr.com/1748/42381064302_206d2a031f_z.jpg) (https://flic.kr/p/27z52Td)

Also ordered a rebuild kit for the carbs last week, from Diablo Cycles. With the thinking that the carbs are virtually identical to the Kawasaki A1 carbs. If not, I have a rebuild kit for sale.  ;D

Only thing left to source are a pare of exhaust pipe gaskets. If anyone has some lying around, let me know.

Next week I'll pull the engin for the last time. I want to measure the total displacement, and work out the uncorrected compression ratio. Then it's wet build time.

Any one have recommendations for oil's? What does everyone use for transmission and pre-mix?
Title: Re: Racer Resurrection
Post by: SR-175 on May 29, 2018, 10:30:22 AM
Hi Al,

You probably know this already, but mentioning it anyway.

The standard SR 22 mm carbs (no chokes) ran a 250 main jet. The Kawasaki A1 carbs (with chokes) ran a 130 / 140 main jet and oil injection. These will be in the rebuild kit. As you will be running pre-mix these will need to be opened up to 250. A 0.057 inch drill bit will make close to a 250 main jet.

I just finished setting up a set of A1 carbs as I wanted to have the chokes for ease of starting.

later ... ray 
Title: Re: Racer Resurrection
Post by: al_pritchard on May 29, 2018, 10:52:50 AM
Hi Ray,

Thanks, I'm still coming up to speed on the carbs so that was new info for me. Thanks, and don't hesitate to tell me things - odds are I will have no idea.

I'm starting to like the idea of switching to A1 carbs in the near future. The choke would be helpful, and I suspect there is some one out there rebuilding a SR that could use a factory part.

A
Title: Re: Racer Resurrection
Post by: bsracer on May 29, 2018, 12:33:56 PM
I usually run from 200-230 main jets in my current 22mm carbs. I think I ran about the same with either the SR 22mm or the A1 22mm carbs. I run Valvoline non-detergent 30wt oil in the gearbox. That's what I've used for almost 15 years now. I started with Motul 800 for premix and I've been using Maxima Castrol 927 for the past 5-7 years. I mix it at 28:1.

You can get almost any jets from Sudco. I have from around 130-300 in mains and a bunch of the various pilot jets for the A1-SR type carbs and the newer style I run (smaller jet). I also have a selection of needles (4 series).


paul
Title: Re: Racer Resurrection
Post by: SR-175 on May 30, 2018, 07:17:25 AM
Hi Paul,

What pilot jet sizes have you played with ?

Hi Al,

As Paul says, best to have a range of main jet sizes to play with, till you find the size that suits the day / conditions you'll be riding in.

ray
Title: Re: Racer Resurrection
Post by: bsracer on May 30, 2018, 10:28:35 AM
Hi Ray.

I was using 17.5 for some time. I've been running 22.5 for the last few years. These carbs (or Rotary valve engines) can be pretty finicky. I have a range from 17.5 to 30 in the style jet for the SR carbs. I thought I had the same for the "newer" style carbs I run but 25 is the largest. I did go up to the 25 when I last raced the bike. I wanted to go bigger to experiment, but I didn't have any 30's to try. I'll check the SR carbs I use to run to verify the jets in them.


paul
Title: Re: Racer Resurrection
Post by: OldSwartout on May 30, 2018, 08:16:56 PM
I ran 230-250 main jets.  The airflow pattern around the carbs will have an effect.  The more protected from high speed airflow past the throats, the more fuel blowback will be drawn back in. If you use the racer carb covers, there will be a fair amount of fuel blown out, but not as bad as leaving them open.

Of course the porting, pipes, etc. make the biggest difference.  I used the basic components; idle jet, needle jet, and needle, of the standard SR 22mm carbs (which were identical to the set of A! carbs I purchased). I then found out there was a severe lean condition at part throttle, probably due to the pipes I was running. I ended up drilling the needle jet out a couple sizes with a drill bit to save pistons.
Title: Re: Racer Resurrection
Post by: al_pritchard on June 08, 2018, 11:02:44 AM
Spent more time in the back yard last weekend than the work shop, we shall see how this weekend goes.

But I did manage to get a little further. Before doing the final build, I wanted to get an idea of the actual head volume. To work out the compression ratio, and start thinking about timing, and fuel.

So the engine is on the bench, and leveled. With the burette carefully positioned over the spark plug hole, and a little grease around the piston edge.

Using a 0.80mm base shim I get a total head volume of 8cc at TDC. This is with an o-ring gasket, the head torked to 5lb, and does not include the volume of the spark plug.

My Set Up
Base Shim: 0.80mm
Cylinder Bore: 50mm
Engine Stroke: 45mm
Exhaust Port Height from TDC: 25mm
Cylinder Volume at BDC: 90.13cc
Cylinder Volume at TDC: 8cc

Uncorrected Compression Ratio: 12.04:1
Trapped Compression Ratio: 7.14:1

To calculate Uncorrected Compression Ratio:
(radius of bore in millimeters) X (radius of bore in millimeters) X (3.14159) X (stroke in millimeters) / 1000 = cylinder volume at BDC
25mm x 25mm x 3.14159 x 45mm / 1000 = 88.36 (88.35721875)

(volume of cylinder at BDC + volume of combustion chamber at TDC) / (volume of combustion chamber at TDC)
88.35cc + 8cc / 8 = 12.04:1 UCCR

Going to try the thiner, and thicker shim this weekend. Will do a test with with no shim as well to get the numbers for all my options.
Title: Re: Racer Resurrection
Post by: bsracer on June 08, 2018, 11:42:53 AM
Check the squish clearance. You don't want it too tight. I think the heads I have on now are at 8cc.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on June 11, 2018, 01:20:41 PM
I dont think I'll have any clearance issues, if anything the "squish" area is non-existent. With no base gasket or shim, and no head gasket I get a 1mm squish at the edge of the piston. Raising to 1.9mm squish, 5mm out. This is probably +/- a little, it was difficult to accurately measure the edge of the solder.


No Shim, No Gasket
Base Shim: N/A
Cylinder Bore: 50mm
Engine Stroke: 45mm
Exhaust Port Height from TDC: 26mm
Exhaust Closes at: 90° BTDC
Cylinder Volume at BDC: 90.13cc
Cylinder Volume at TDC: 7.1cc

Squish:
At Cylinder Wall: 1mm
5mm From Cylinder Wall: 1.9mm

Uncorrected Compression Ratio: 13.45:1
Trapped Compression Ratio: 8.19:1


Small Shim, No Gasket
Base Shim: 0.61mm
Cylinder Bore: 50mm
Engine Stroke: 45mm
Exhaust Port Height from TDC: 26mm
Exhaust Closes at: 88° BTDC
Cylinder Volume at BDC: 90.13cc
Cylinder Volume at TDC: 7.5cc

Squish:
At Cylinder Wall: 1.61mm
5mm From Cylinder Wall: 2.51mm

Uncorrected Compression Ratio: 12.78:1
Trapped Compression Ratio: 7.81:1


Medium Shim, No Gasket
Base Shim: 0.80mm
Cylinder Bore: 50mm
Engine Stroke: 45mm
Exhaust Port Height from TDC: 26mm
Exhaust Closes at: 86° BTDC
Cylinder Volume at BDC: 90.13cc
Cylinder Volume at TDC: 7.8cc

Squish:
At Cylinder Wall: 1.8mm
5mm From Cylinder Wall: 2.7mm

Uncorrected Compression Ratio: 12.33:1
Trapped Compression Ratio: 7.54:1


Thick Shim, No Gasket
Base Shim:
Cylinder Bore:
Engine Stroke:
Exhaust Port Height from TDC:
Exhaust Closes at:
Cylinder Volume at BDC:
Cylinder Volume at TDC:

Squish:
At Cylinder Wall:
5mm From Cylinder Wall:

Uncorrected Compression Ratio:
Trapped Compression Ratio:


(https://farm2.staticflickr.com/1737/41835280485_478f8cdd52_z.jpg) (https://flic.kr/p/26JQKnp)
Title: Re: Racer Resurrection
Post by: al_pritchard on June 25, 2018, 07:03:29 PM
Started disassembly, and cleaning of the carbs. Thought I'd share some numbers:

SR Carb
Needle - 4J6
Needle Valve - 2.0
Pilot Jet - 30
Main Jet - 220

From the kit
Needle - ??? No idea, it's not stamped
Needle Valve - 2.0
Pilot Jet - 30
Main Jet - 130, 140, 150

Needle Jet - Wow am I not happy about this. It's has a bur inside

Overall not happy with the quality of the parts in this ket, and would only recommend if you needed some of the other bits.

Quick question, when striping down the carb. How do you safely remove the needle jet? I'v seen a couple of youtube videos that show it getting "lightly" hammered up - using a wood dowel against the seat. How much resistance should I expect? I'v given it a couple of taps, but nothing of any real force.
Title: Re: Racer Resurrection
Post by: BRT-GTR on June 26, 2018, 09:39:10 AM
       Al,
             I did push a couple of needle jets out of slightly corroded 350 carbs, 12 months ago, to see how easily they would come out and clean them.
        One moved with a couple of light taps, second required a little bit more welly.
       You will know this but make sure you first remove the thick brass washer under the main jet. I then put an old main jet back in and hit this, using a piece of hard wood, to move the needle jet, sure I used a piece of dowel to complete the push out.
      Seem to remember, they only needed driving for the first 10mm or so and then loosened up. They are a light push fit when replacing, main jet and washer was used to fully seat them.
      Difficult to advise on force require but feel you have enough hands on experience to know when to back off.                                                           Brian.
Title: Re: Racer Resurrection
Post by: bsracer on June 28, 2018, 09:57:07 AM
There is a pin in the carb body that locates the jet. The jet should have a slot. Sometimes there can be some crud making it difficult to remove. I think I used a small size nut driver and get them moving. Not ideal. You could make up a dowel out of delrin or something like that to tap on the jet so you don't damage the threads or jet.

paul

p.s. where did the kit come from?
Title: Re: Racer Resurrection
Post by: moonpup on June 28, 2018, 10:15:11 AM
On some difficult ones I had, it helped to boil up some water and let them soak in there for a bit. I also sprayed some WD-40 down that slot/channel Paul mentioned.

Some tapped out with a wooden dowel, while others required the sacrificial main jet like Brian used.
Title: Re: Racer Resurrection
Post by: OldSwartout on June 28, 2018, 02:09:24 PM
I generally use a 1/4 ratchet extension. They're slightly rounded on the tip, just enough to prevent damaging the threads and nearly the same size as the hole in the carb.  The one disadvantage is they are large enough diameter to push the little brass locating pin partially out and you have to remember to push it back in later. 

I like the sacrificial main jet idea better.
Title: Re: Racer Resurrection
Post by: BRT-GTR on June 28, 2018, 02:59:53 PM
         Against expectations, the main jet didn't suffer any damage and is now back in my collection. It was a 160 I found in one of my spare carbs, likely a younger rider trying extract more power from his GTR back in the day.                                Brian.
Title: Re: Racer Resurrection
Post by: al_pritchard on July 07, 2018, 04:16:38 PM

Foiled again.

With the next week off, I was attempting to finish the engine build. And perhaps start the bike. But that does't look like it's happening.

Everything together, and lightly oiled. Everything spins smoothly. But.... I have a leak or two.

While pressurizing the left cylinder, I found a leak at the right crank seal. So I guess that means, I need a new crank seal. And I guess I need to swap out the crank for the NOS one. Hoping that seal is still good.

I send an email off to Richard, and I'll follow up monday with a call. But if anyone has any of the following, I'm interested.

#27
1451-8000
Crank Shaft Color
(This is precautionary, but it looks a little worn so if I can find one)

#32
09090-109
28 Oil Seal

Paul - The kit came from Diablo Cycles up in Canada.


Couple of photos to keep everyone engaged.

(https://farm2.staticflickr.com/1829/29392611518_1f3585d857_z.jpg) (https://flic.kr/p/LMjPo7)

It looks like the rotary disk was already trimmed to the specification in the tuning guide
(https://farm2.staticflickr.com/1801/29392615538_0864ea6c8b_z.jpg) (https://flic.kr/p/LMjQzq)

(https://farm2.staticflickr.com/1825/29392618278_c38fe8a528_z.jpg) (https://flic.kr/p/LMjRoE)

Translating degrees to the dial
(https://farm1.staticflickr.com/914/28393273897_65f4aa1685_z.jpg) (https://flic.kr/p/Kg1X88)

(https://farm2.staticflickr.com/1824/28393275477_3c984e64fe_z.jpg) (https://flic.kr/p/Kg1XAn)

And clean carbs. Reused the old jets - they looked very clean.
(https://farm2.staticflickr.com/1788/28393276837_995b01fdc2_z.jpg) (https://flic.kr/p/Kg1XZP)

P.s. Managed to get the main jets out. Need to look closer at the parts diagram, I completely missed the washer - Thanks Brian.
Title: Re: Racer Resurrection
Post by: bsracer on July 10, 2018, 09:10:01 AM
Hi Al,

well I thought I wrote a response yesterday but it seems to be gone now?

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on July 11, 2018, 08:15:47 AM
I got the email notification you did. But I never saw the post.

On the plus side, a full set of Oil seals have been ordered. So the engine comes apart this week for a second rebuild. With my last crank. Let’s hope that seal is still good, otherwise.....
Title: Re: Racer Resurrection
Post by: al_pritchard on July 23, 2018, 11:36:13 AM
All the new seals are in. Thanks Richard!

Went to pull the bearings off the crank to transfer onto the NOS crank. I can feel a little lateral movement in the bearing. So I'm going to pick up new ones before I assemble everything. Hopefully for the last time before starting. It looks like the outer bearings are pretty standard. So I should be able to source locally, unless anyone knows of a good distributer. Or a reason to order NOS bearings from Richard.

My last crank is slightly different than the other two. And I think that may lead to me needing to do additional work. The other two cranks have a grooved center bearing, the NOS crank has a centering hole, and an oiling hole but no groove. I asume that the oiling hole in the bearing needs to align with the hole in the upper case, and the centering hole helps achieve that.

I think I saw a reference to aligning by hand in another thread. Am I foolish for attempting that? Should a align by hand, and use a little green lock tight to prevent the bearing form spinning. Or am I on the hunt for a new case, or off to find a good machines?

NOS Crank on top
(https://farm3.staticflickr.com/2924/33226604310_3993f622a6_z.jpg) (https://flic.kr/p/SC82S7)

Upper Case
(https://farm3.staticflickr.com/2843/34288433925_4c48499956_z.jpg) (https://flic.kr/p/UeXbPg)
Title: Re: Racer Resurrection
Post by: OldSwartout on July 24, 2018, 06:02:26 AM
The NOS crank is the later design.  There is supposed to be a dowel in the lower crankcase half to locate the bearing and keep it from rotating. That maintains alignment of the bearing oiling hole with the feed hole from the upper case.  The earlier version relied on the oil/fuel mix traveling around the bearing outer groove to the oiling hole in the race.  I never heard an official reason for the change, but could guess that the bearing in some of the early version may have moved axially in operation or been misaligned toward the seal when assembled, resulting in cutting off the oil feed.  If you use the later crank, you should have the dowel in the lower crankcase half and won't need the half ring in the upper case, if you use the earlier, loctite the bearing in place.
Title: Re: Racer Resurrection
Post by: dcr on August 01, 2018, 10:58:50 AM
I have a similar situation. The original motor in my 175DT has the old style center bearing. I have been going back and forth on a resolution and need to decide on having a crank rebuilt with a "new" old style center bearing OR having the case drilled to accommodate the locating pin on the "new" style center bearing since I have a really good crank with that style center bearing.

I would imagine the new style center bearings are more plentiful so that may be the way for you to go? I have several of them but was only able to locate 1 of the old style.

Dan
Title: Re: Racer Resurrection
Post by: al_pritchard on August 01, 2018, 03:22:01 PM
I'm in the same place Dan.

I have 3 cranks, two with the new bearing, and one with the old. I think I'l be sending the case out to have a pin added.

On a side note. Went looking on eBay for an alternative engine case, with a pin. Holy S&%#! They want a lot of money so some very dodgy looking parts.
Title: Re: Racer Resurrection
Post by: dcr on August 02, 2018, 03:41:27 PM
Al - I have a case I'd part with that has the locator pin. It's in really good shape as I recall, but I'd have to double check. I bought a motor off a guy a few years back but I don't really have a use for it.

Send me an email at droth at hmcontrol dot com if you are interested. Ill send you pictures and you can decide.

Dan
Title: Re: Racer Resurrection
Post by: al_pritchard on August 13, 2018, 11:10:45 AM

Big thanks to Dan! My new to me case arrived without a scratch. Eventually I’ll have the old case machined for an index dowel. But for now this case should same me some time.

Everything looks identical between the two. Except for the timing idle gear shaft. The old case has a “plug” in the spot the new case has the timing idle gear shaft. Does anyone have any thought on how to remove the shaft? It looks like I might be able to press it out from the back. Alternatively, I could cut it off but that seems drastic.

Quite The Packing Job - Looks like it was customer made for the case
(https://farm2.staticflickr.com/1798/43965905832_37af71d3f8_z.jpg) (https://flic.kr/p/29Z7L4b)

Upper Case Half - With idle gear shaft
(https://farm2.staticflickr.com/1820/43965904792_d9b7990c4b_z.jpg) (https://flic.kr/p/29Z7KKf)

New vs Old - The new case has the index dowel for the center bearing
(https://farm1.staticflickr.com/929/43965907052_1733813dac_z.jpg) (https://flic.kr/p/29Z7Lqd)
Title: Re: Racer Resurrection
Post by: OldSwartout on August 14, 2018, 08:31:10 AM
One possibility to remove the shaft if you don't come up with something better: weld a nut on the end and use a slide hammer to pull it. I'd put the case up against something solid like vice jaws, both for inertia and to prevent possibly breaking the case.
Title: Re: Racer Resurrection
Post by: dcr on August 14, 2018, 09:01:30 AM
Al, just my opinion here, but I would cut the shaft off as close to the case as possible and then mill it off flush.

If you press it out and manage to avoid cracking the case, you will still have to plug the hole with something. Going the cut off route seems to me to be the least risky move.

Dan
Title: Re: Racer Resurrection
Post by: al_pritchard on August 14, 2018, 05:08:38 PM
I think cutting it off, and “milling” it flush is going to be the easiest. I put quotes around milling, because I don have a mill. But I think I can get away with an end mill on the drill press, and plunge cut it. I have a good x z vice that should help. And I figure if I only plung cut, the drill press should be able to handle it.
Title: Re: Racer Resurrection
Post by: OldSwartout on August 14, 2018, 07:31:24 PM
It only needs to clear the driven gear on the end of the alternator.  Just clip it off with a cutoff wheel in a die grinder and get it relatively flush. There is a reasonable amount of clearance behind the gear and you can easily check it visually. It's not necessary to go to all the trouble to set up a mill cutter.
Title: Re: Racer Resurrection
Post by: al_pritchard on September 13, 2018, 04:13:07 PM
Figured a quick update was in order. Not a lot of progress on the engine, but all the parts are in. And that pesky shaft/nub is no longer in the way.

Most of last weekend was spent at NJMP watching the super bikes play in the rain. Interestingly 3 of the last 4 MotoAmerica races in NJ were in the wet. The USCRA guys were also in attendance, and like last year It was fun watching them go round.

I did manage to find a little time between rain drops on Friday to put the final coat of clear on. Ended up going with white. I think it looks rather nice with the big Bridgestone markings.

The under lying color is your standard Rustoleum. With a top coat of USC 2K high gloss clear. Very impressed with how this went on. It’s a 2 part clear, you “pop” a button on the bottom of the can shake for 2 min, and spray. And it’s full proof - I hope.

(https://farm2.staticflickr.com/1855/30792183208_958280cc49_k.jpg) (https://flic.kr/p/NUZZhu)

(https://farm2.staticflickr.com/1900/30792183378_46084860fa_k.jpg) (https://flic.kr/p/NUZZkq)
Title: Re: Racer Resurrection
Post by: rwgibbon on September 14, 2018, 07:13:17 AM
Very nice!
Title: Re: Racer Resurrection
Post by: al_pritchard on September 27, 2018, 02:01:27 PM
Thought I was making such good progress over the last two weeks. The “nub” has been removed, everything is scrubbed clean and oiled up. All new seals, and even new head studs. Assembly was moving smoothly, then…

 :'(

I striped out the cylinder head stud hole in the block. I’m going to try to open it up, and install a helicoil without stripping the engine down again. Otherwise it all comes apart, and gets resembled again.


(https://farm2.staticflickr.com/1903/30016181517_c3be4c2ab1_c.jpg) (https://flic.kr/p/MJqM1Z)

(https://farm2.staticflickr.com/1966/30016180767_97cd8ccdc7_c.jpg) (https://flic.kr/p/MJqLN4)

(https://farm2.staticflickr.com/1930/30016180027_ffb2b6e3f3_c.jpg) (https://flic.kr/p/MJqLzi)
Title: Re: Racer Resurrection
Post by: OldSwartout on September 27, 2018, 07:08:30 PM
Damn!  Yes, helicoils work for that, and it really shouldn't be hard to keep the chips out of the bottom end. I've done one or two over the years.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 11, 2018, 01:25:27 PM
Whats that saying, use the right tool for the job?

After 7 un-successful attempts with the original “official” Helicoil kit. I ordered an e-z coil kit. First attempt, success! The e-z tool keeps the coil comprised as it threads into the hole. The helicoil tool does not have a way to keep compression on the coil. So it expands, and attempts to cross thread the hole.

So product recommendation. If you want to use a coil based thread prepare method. Get eh E-Z Coil kit.

To do it all over again, I would probably get a Time-Sert kit. I like the idea of having the top hat that time-sert provides. In the case of the coil, you need to install it slightly below the top of the hole. Not a bit deal in most cases, but the head stud is slightly narrower than the hole needed to install the coil. So the stud is going to be slightly shorter by a thread or two. Shouldn’t be an issue.

Now I can get back to building this engine.

Massacred Helicoils
(https://farm2.staticflickr.com/1911/45250004581_192db38935_c.jpg) (https://flic.kr/p/2bWA6SM)

Get this tool!
(https://farm2.staticflickr.com/1953/44527676544_4e8942337a_c.jpg) (https://flic.kr/p/2aQKYV7)

It makes this easy
(https://farm2.staticflickr.com/1946/44527676714_85b28fda43_c.jpg) (https://flic.kr/p/2aQKYY3)

And fixed
(https://farm2.staticflickr.com/1974/44527676334_e06dd33053_c.jpg) (https://flic.kr/p/2aQKYRu)
Title: Re: Racer Resurrection
Post by: al_pritchard on October 15, 2018, 01:16:36 PM
Managed to steal a couple hours over the weekend - double duty watching WSBK, and building an engine.

One of the nice surprises that came with the spares package is a packet of new SR clutch plates - Thanks Richard! It’s good to, because two of the plates that were in the bike were broken.

Assembly is going smooth, with everything seeming to fit where it should. Fingers crossed…


(https://farm2.staticflickr.com/1961/31468113878_ca563c34bc_c.jpg) (https://flic.kr/p/PWJiVy)

(https://farm2.staticflickr.com/1957/31468114058_4e4f51c862_c.jpg) (https://flic.kr/p/PWJiYE)

(https://farm2.staticflickr.com/1952/31468113298_e684a2db39_c.jpg) (https://flic.kr/p/PWJiKy)
Title: Re: Racer Resurrection
Post by: al_pritchard on November 06, 2018, 06:54:56 PM
I guess third times the charm.  ;D

It seems that the oil seal on the transmission output shaft needs to be put in place, before the case haves are joined. Lesson learned. So, now that we have everything back to gather again, I have a question.

I'm using the aluminum shims from Cometic, between the case and the cylinders. Should I also be putting a little Yamabond on both sides of the base shim? Or will the aluminum of the shim be soft enough?

Oil Seal
(https://farm2.staticflickr.com/1910/45706600662_7e6918e268_z.jpg) (https://flic.kr/p/2cCWgZ1)
Title: Re: Racer Resurrection
Post by: OldSwartout on November 07, 2018, 08:17:44 AM
IMO, go with Yamabond or something similar, won't hurt and may prevent an air leak that could cost you a piston and cylinder. If a head gasket leaks, you'll see it and it won't destroy your engine.  A cylinder base leak might.
Title: Re: Racer Resurrection
Post by: bsracer on November 10, 2018, 03:07:43 PM
This is what I
use on the heads and on the aluminum base shims.

paul

https://www.permatex.com/products/gasketing/gasket-sealants/permatex-copper-spray-a-gasket-hi-temp-sealant/
Title: Re: Racer Resurrection
Post by: OldSwartout on November 10, 2018, 07:34:05 PM
This is what I
use on the heads and on the aluminum base shims.

paul

https://www.permatex.com/products/gasketing/gasket-sealants/permatex-copper-spray-a-gasket-hi-temp-sealant/
Agreed - that's what I used on head gaskets. I didn't think about it for the aluminum spacers, but makes sense.
Title: Re: Racer Resurrection
Post by: al_pritchard on November 13, 2018, 12:10:11 PM
I used a copper spray on the head gasket when I restored the Jeep. It worked - and still is working - very well. Didn't even think to use it for the base shim. Might transition to it when I pull the heads off next time. The Yamabond is a little messy, and not very good at transferring heat.

I did manage to get the engine all buttoned up this weekend. Fingers crossed I did it right. Also set the static timing to 24° BTDC (2.356mm or 0.092in BTDC) The photo below shows the magnet rotated to about TDC. The Dyna fired about when the blue line gets to the raised edge of the pickup. I may go in, sand off the blue lines, and reposition them to allow me to mark the timing on the pickup. For now it's marked on the side of the generator case, and the engine case - blue marks.

Also started practicing my safety wiring skills.

(https://farm2.staticflickr.com/1973/45139027144_17d2a1113e_z.jpg) (https://flic.kr/p/2bLMj9G)

(https://farm5.staticflickr.com/4867/45139027034_5c133f3dfe_z.jpg) (https://flic.kr/p/2bLMj7N)

(https://farm5.staticflickr.com/4876/44950272345_749a60e62b_z.jpg) (https://flic.kr/p/2bu6TVB)

(https://farm2.staticflickr.com/1969/45139027444_4681c6135b_z.jpg) (https://flic.kr/p/2bLMjeS)
Title: Re: Racer Resurrection
Post by: craig641 on November 14, 2018, 10:43:18 AM
Double check your safety wiring on your exhaust studs.  The one on the right is wired so it's loosening the nut, not tightening it.
Title: Re: Racer Resurrection
Post by: al_pritchard on November 24, 2018, 05:07:53 PM
Yea. Di that wrong. :(

The learning curve is steep... I think I got it right this time. Having to re-do the safety wire also made me aware of the lack of spring hangers. Not sure how the PO had the springs mounted before. But by the length of them, I suspect they were around the castings in the cylinder.

Lets see if these work better.
(https://farm5.staticflickr.com/4807/45308762434_63a53b3070_z.jpg) (https://flic.kr/p/2c2Mfxd)

If I did all the math correctly, I should be at 24° BTDC at 0.092in. I couldn't find a measurement for the 175 crank anyway, but I thought it was about 100mm.

Karl, Paul, do you have a measurement for the crank length?

(https://farm5.staticflickr.com/4814/45983203232_f50846af3f_z.jpg) (https://flic.kr/p/2d4nWhQ)
Title: Re: Racer Resurrection
Post by: bsracer on November 25, 2018, 12:15:54 PM
The rod length is 100mm. There are formulas to calculate the deg BTDC vs the value in mm. I run 2.0mm BTDC, not sure what that equates to deg wise (Karl's the engineer). With dial indicator in plug hole find TDC. Rotate backwards 2.0mm on dial and set timing. My ignition is setup with a taper adapter. When I set the indicator to 2.0mm BTDC I just line up the mark on the rotor to the one on the stator and I'm done. When the ignition housing is set in the "middle" you can advance or retard the timing by rotating the whole assembly. I tried those figures in the Bridgestone tuning manual years ago but have always been on the conservative side on the timing. I have run from 2.4mm down to 1.8mm BTDC. I haven't changed it from 2.0mm for some time. With all the other issues, I just try to keep some variables constant.

paul

p.s. I ran 32:1 vs 28:1 at Barber this year because I was sharing fuel with a friend. Not much of a difference in oil (.5oz per gallon). The bike was already running rich and I did not re-jet. Left side bottom end bearing seized on first lap of Fri practice. Replaced the crank and missed two races. In the fourth race on Sunday the RH big end bearing seized up. Some bearing fragments did make it to the head on the first seizure. Cleaned it up and back together. I mostly kept the bike under 12K and it was going ok, but not in the real power band. No other real damage was apparent after both seizures. In fact the burn pattern on the new heads was very good. Both seizures happened at pretty much full throttle on straights. One factor was that these were stock cranks. I've had the same thing happen once before (32:1 and stock crank). The crank I built with Yamaha KT100 rods was way out of true upon inspection prior to Barber. The first crank was in my spare engine. It had been run once after a piston failure at Sonoma. The second crank was an original SR crank that was repaired with a double stepped pin that Karl had made. I broke a similar one and never ran this because I thought it might break as well. It also had an untested labyrinth seal.

At least I know the labyrinth seal works! Back to the drawing board on the crank modifications. I'm going to maybe try stepped pins on one and another crack at 20mm holes bored out. I think they will be ok if executed properly this time.
Title: Re: Racer Resurrection
Post by: al_pritchard on November 26, 2018, 09:59:24 AM
That puts us pretty close Paul.

2.0mm = 22°
2.365 = 24° - From the manual

Good point about leaning a little conservative with the timing. Might follow your lead here.

By the way a handy little calculation tool at: www.torqsoft.net/piston-position.html. I subscribed to the site for a while, when I wanted to try to understand what the modifications from the manual would do. But some of the tools are free.

I'm getting more and more worried about the cranks. Very interested in seeing how the two of you move forward. Especially because I'm down to my last one.
Title: Re: Racer Resurrection
Post by: bsracer on November 26, 2018, 12:05:02 PM
You will probably be ok for a while. I think something is wrong with the setup on my bike. Mostly the pipe and maybe carburation. I'm confident the newer style crank will work, it just wasn't executed properly. I found a guy in LA/Orange County that has 45 years doing jig boring/grinding. I think he can do the holes in the crank with better precision. I really need to take the approach of figuring out what's going on in the motor for next year.


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on December 04, 2018, 04:50:32 PM

Progress continues. I didn't notice this before, but their is a bit of wear on the side the the gear. And it's only on the drive gear. You can't see it that well in the photo, but it looks like the engine is cocked slightly left - forward to the left, rear to the right.

I don't feel any binding, but you can hear the "tick, tick, tick" from the chain. Anyone care to hypothesize on the problem? Twisted swing arm, bent frame?


(https://farm5.staticflickr.com/4848/32309179518_e222826efd_z.jpg) (https://flic.kr/p/Re3Zrh)

(https://farm5.staticflickr.com/4868/32309179548_4a729dfb8c_z.jpg) (https://flic.kr/p/Re3ZrN)
Title: Re: Racer Resurrection
Post by: srpackrat49 on December 04, 2018, 09:59:59 PM
That is normal were,,,,,, just put the dam thing on the track and tell us how runs,,, in a year or 2 !!!!!
Title: Re: Racer Resurrection
Post by: BRT-GTR on December 05, 2018, 09:11:36 AM
          Had similar issue with the GTO when I got it :-     Chain 'chunnering' on the front sprocket when wheel spun, sprocket worn on one side only and a bonus of a clang every time the split link passed/hit the forward chainguard bolt  :D :D.
          Turned out to be a combination of the engine skewed to the left (worn engine mount bushes) and bad rear wheel alignment.     

 First of all, line up the rear wheel with the front using a plank or string (care at this stage ensures the bike steers straight, hands off) then check the sprocket alignment. Books say use a straight edge but not possible on our machines, too many items in the way, so sight it or try a piece of thin cord. Laser tools are available.

   I wouldn't use that sprocket, looks severely worn, teeth slightly hooked ?  Does your chain clear the rear shock, looks very close.
Title: Re: Racer Resurrection
Post by: OldSwartout on January 12, 2019, 08:35:06 PM
175 Crankshaft Degrees vs. piston stroke from TDC.
Title: Re: Racer Resurrection
Post by: al_pritchard on February 13, 2019, 04:16:33 PM
When we last tuned into our program...

WARNING - If you have a crease, or a crack in your tube. Don't do this. Go get a new tube.

Im my continued failed attempt to align my rear wheel with the front wheel. I came to the realization that the fork tubes were a little bent. Making it exceedingly difficult to get the front spaced equally between the forks. Not out a lot, but just enough that by the time you get to the end of the fork tube it was easily noticeable.

Since I couldn't find a shop willing to straighten them. It was time to buy a small press. I would encourage anyone with this issue to "do it yourself". The process was super simple. Plan the tube on a set of v-blocks ($40 on eBay). Get out a dial indicator to find the high/low spot - slowly rotate the tube in the v-blocks and keep an eye on the indicator. My bend was just below the lower triple clamp. When you identify the true high spot, start pressing - gently. I would put a little pressure on the tube. Release. Then rotate the tube to see how much bend I took out. Keep repeating the process until you get the bend out.

It's a good idea to put something between the tube and the ram - v-block made out of wood, strip of wood, thick gasket material, what ever. You just want to keep the ram from making the chrome.

So tubes are now 0.009in and 0.008in out. Or to make it sound better, on side pushes in 0.0045" in, and the other side sticks out 0.0045in. I can live with that.

Now back to aligning that rear tire. Spring is going to be here soon, right. I'm dying to start this thing.

(https://farm8.staticflickr.com/7861/46362368424_b57cf9ce1e_z.jpg) (https://flic.kr/p/2dCTfTJ)

(https://farm8.staticflickr.com/7855/46362368334_e936cf1390_z.jpg) (https://flic.kr/p/2dCTfSb)

(https://farm8.staticflickr.com/7863/46362368174_fe7a973701_z.jpg) (https://flic.kr/p/2dCTfPq)
Title: Re: Racer Resurrection
Post by: al_pritchard on March 11, 2019, 03:15:34 PM

Not a lot to report on. Everything is finished, just need to add oil and fuel. So stay tuned for warm weather and an update on the starting front.

(https://farm8.staticflickr.com/7911/47296243602_89354fc761_z.jpg) (https://flic.kr/p/2f4pBrU)

I added a set of quick disconnects for the fuel lines. Will probably replace then once the big gremlins are worked out. I couldn't work out a tidy way to have both the quick disconnects and a T connector. I'm currently assuming that the tank will be on and off a lot in the beginning, and the quick disconnects will be valuable.

(https://farm8.staticflickr.com/7906/33472918118_4a25e992f5_z.jpg) (https://flic.kr/p/SZTsnU)
Title: Re: Racer Resurrection
Post by: Jeff Bar on March 11, 2019, 03:59:19 PM
Al. You really do nice work, everything looks so good I am pretty decent at general restoration but wish I do you level of fab work thanks for posting I really enjoy looking at your post. Jeff bar
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 13, 2019, 01:26:42 PM
Ditto the appreciation for all the build information.  I just stumbled into a Mach II RS that's just bad enough off to justify some customization instead of pure restoration, and although I've been around bikes all my life (I'm an old guy - 75), this is my first BS.  It's really nice to see what's available, what works, etc - I've wanted to add a little two stroke to my garage, and this was the perfect candidate.
Title: Re: Racer Resurrection
Post by: Mike Anderson on March 13, 2019, 03:47:00 PM
Pictures as it goes. Good luck with the project
Later Mike
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 13, 2019, 10:22:59 PM
I just happen to have a couple Kehein PE26's from KX100's and am contemplating how they might be mounted to custom disc covers with the shortest inlet tract possible (I have a very nicely equipped machine shop focused exclusively on motorcycles) - anyone experiment with other carb's this large?  Also, the factory Tune up manual provides dimensions for a couple variations of expansion chambers for 175's, do you happen to have this info for 200's?  A few years ago I hydroformed a megaphone exhaust for a project and have wanted to try making a pair of expansion chambers, ever since.  The bike has great compression on both cylinders and shifts perfectly, but I plan to take it down to the crank, anyway - this bike will get used regularly so I'd like to start from the inside out - especially if I'm going to lean on the engine.
Title: Re: Racer Resurrection
Post by: bsracer on March 14, 2019, 11:23:42 AM
You might be able to run some 26's but there's a lot of other work to be done. I run 22mm because AHRMA has a restriction on the Bridgestone for the class I run. The info in the tuning manual is a bit outdated these days for expansion chambers.

paul
Title: Re: Racer Resurrection
Post by: OldSwartout on March 14, 2019, 11:51:29 AM
You might be able to run some 26's but there's a lot of other work to be done. I run 22mm because AHRMA has a restriction on the Bridgestone for the class I run. The info in the tuning manual is a bit outdated these days for expansion chambers.

paul
I agree with Paul, the expansion chamber info in the tuning manual is outdated, although it worked OK back in the day.  Modern chambers are larger diameter, with tapered head pipes, multiple tapers on the cones, etc.  The first set my brother and I built for my racer based on Bell's Two Stroke book seemed to work OK, but I found out later the  power curve had a BIG drop in the 8-9000 range.

There are a couple issues with 26's: space in the housings and difficulty getting a matching port area going into the crankcase.  It's difficult getting a corresponding passage to match the 22's, the radial distance you have to work with is limited.  I think you would end up with a 26mm carburetor feeding the engine through the equivalent of a 22mm orifice in the crankcase wall.
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 14, 2019, 07:29:42 PM
Beautiful valve covers, I hope I can produce something along that line.  I was a Suzuki Can Am Vespa dealer in the 70's and had fun building rotary valve Can Am's, so this is a blast from the past in more ways than one.  Yeah, I agree about the carbs - I just happened to see them lying there, alone, waiting...  Anyway - like I said, I want a bike I can have fun with while I'm dodging Buick bumpers.  It'll stay a 'sit-up standard' but tucked in a little, solo seat, etc with slightly updated suspension hidden as best possible.  Any links to the expansion chamber dimensions with comments about their power characteristics would be greatly appreciated.  Obviously related, since the stroke is the same as the 175, is the porting info reasonably useful?  Since this bike doesn't have to meet race or show class restrictions I'm guessing I might have a few more choices throughout the build - I just want to stay somewhat faithful to the basic bike and was delighted to find this group of enthusiasts.  Thanks, guys...
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 24, 2019, 09:00:43 PM

Yea!!  Looks like the title is no problem, so I'm ready to start on the 200 project.  I'll pull the motor completely apart for at least a fresh top end and porting & intake rotor trim along the lines of the scrambler section of the tune-up manual.  I also like ceramic in exhaust ports & combustion chambers, so maybe that as well.  After reading the discussion about the stepped center pin, if my crank needs anything I'll do that mod, and am very interested in the recommendation for RM100 rods and pistons.  The KX100 26mm carbs I mentioned earlier will physically fit in both sides (I wasn't sure about the right-side case), so now I need to decide if a mildly ported motor with only a moderate compression increase use that much carb.  In the meantime, I'd like to start fabbing the pipes - I see several discussions about pipes and how they've evolved, anyone willing to suggest dimensions for something oriented towards mid and upper mid-range?

Thanks, Art
Title: Re: Racer Resurrection
Post by: vinny g on March 25, 2019, 06:13:24 PM
Hi Art. I did a post a couple of years back, on here, about the specifications of my 175/200 racer including the spec of my pipes. I'm on my phone and unable to find it for some reason, but type UK 200 racer into search and it may help you. Alternatively, search via my name. Anything you need to know, tune up wise, is on that post and tried and tested.

Cheers, Vince

Keep up the good work, Al! Bike is looking good!
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 26, 2019, 05:11:42 PM
Hi Vince - thank you very much - I'll do update posts & pic's once I finally start pulling things apart, but should the top end need drastic work, anyone care to comment on the maximum safe overbore (again - no race rules, this is a street bike)?
Title: Re: Racer Resurrection
Post by: OldSwartout on March 26, 2019, 05:31:44 PM
Sounds like a fun project and Vince's specs should make a really fast bike.  As far as overbore, since those had a chrome bore, Bridgestone didn't make oversize pistons for the 200, so you'd have to look for something from another brand. You would have to consider piston pin size, deck height, crown and overall length. Vince's post said he ran modified Suzuki X7 or Kawasaki KX100 pistons, so start there.
Title: Re: Racer Resurrection
Post by: anotheroldtrailrider on March 27, 2019, 09:05:16 PM
Hi Karl - I was referring mostly to minimum cylinder wall thickness prior to re-coating in the question about overbore limits and doubt that's needed.  Obviously I haven't done much research on piston dimensions yet, but the KX and RM suggestions included head and cylinder deck mods to accommodate them.  Your mention of overall piston dimensions fits right into their discussion about port timing changes when the cyl is trimmed on the bottom vs on the top - obviously depends on piston dimensions like you said...hmmm, I gotta lot to learn on this one...
Title: Re: Racer Resurrection
Post by: al_pritchard on May 06, 2019, 10:01:02 AM
With a small window of sun shine on Saturday, we drug the bike out of the workshop for it's first start. Unfortunately it didn't go completely to plan.

Set Up
Pilot Jet: 20
Main Jet: 230
Air Screw: 1 1/4 turns out
Float: 25mm
Fule: 112 octane / VP C12
Oil: 28:1 / Castor 927

I did manage to get it turned over twice, but immediately bogged and died after hitting 4000 RPM. I think a lot of this is due me being to heavy on the throttle as it would start to catch.

I checked the timing was at 0.09" / 24° BTDC, and I had good , strong spark. As an aside, make sure you ground the spark plug on the side of the head, or it will ground through you. Ask me how I know.

Im thinking of stepping up to the #25 for the pilot jet, and stepping down to the #220 main jet. And turning the air screw 2 1/4 turns.

The good news is that my drive way has a slope. So pushing is not that hard. And I get a good long 50 foot for two, or three attempts per push.

Questions / Thoughts
This is the first time I've set up a carb. Should the slide be resting on the floor of the carb, or should is be raised slightly? That didn't seem clear to me. Nor did the air screw. Some set ups from the carting world talked about 2 1/2 turns to start with. And I think the Sudco book stated 1 1/4.

(https://live.staticflickr.com/65535/46999162234_316c851664_z.jpg) (https://flic.kr/p/2eB9Zvm)
Title: Re: Racer Resurrection
Post by: al_pritchard on May 07, 2019, 11:15:01 AM
A short video, sound will help. It catches and then dies.

Click on the image to view the video
(https://live.staticflickr.com/31337/33919913068_86d8df7457_z.jpg) (https://flic.kr/p/TFoqpo)
Title: Re: Racer Resurrection
Post by: BRT-GTR on May 08, 2019, 08:59:01 AM
          Bike looks great.
       Here's a link to a good carb tuning guide that I found helpful when setting up my GTO carbs from scratch.
                http://kawtriple.com/mraxl/carb/carbadj.htm (http://kawtriple.com/mraxl/carb/carbadj.htm)

    Put the 25 pilots in (airscrews 1 1/2 turns out) and raise the carb slides a turn or two to see if you can get her to stay running. Leave the big main jets in until you are happy with the pilots/carb slide cut outs/jet needle postion. Main jets are the last items to tune.
Title: Re: Racer Resurrection
Post by: bsracer on May 08, 2019, 12:27:07 PM
Hey Al, what needles do you have and what position are the clips in?
These carbs seem to be very finicky. If the needle is a 4L6 it may be too rich. I typically run the mixture screw barley a 1/4 turn out. I just tried up to 35 pilots at Willow. It would be fine on start up and slower running but anytime the throttle was closed from WO it was too rich. I ended up back to my almost regular carb settings. I did leave a 25 pilot in (I'd usually run a 22.5). You can turn the idle screws up so it will idle then adjust mixture screws.

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on May 09, 2019, 01:18:19 PM
Thanks for the link Brian. I think this might help a bit with the learning curve.


Available Jets
Pilot
17.5 ( VM22/210)
20 ( VM22/210)
22.5 ( VM22/210)
25 ( VM22/210)
27.5 ( VM22/210)
30 (Original)

Main
230 HEX ( 4/042)
240 HEX ( 4/042)
250 HEX ( 4/042)
300 (Original - although one seems much smaller)

The carbs were set up with a 30 pilot just, and a 300 main when I got the bike. But with a blown engine, I never ran it with that setup. I swapped them out because the pilot head screw slot looked like my dog chewed on it. And one of the 300 mains looks much smaller than the other - even the carb cleaning wire didn't open it up. So it might be miss labeled, or just hopelessly clogged.

I don't know what the needle is. I'll swap out the pilots and check the needle. Stay tuned...
Title: Re: Racer Resurrection
Post by: al_pritchard on May 10, 2019, 09:13:22 AM
The needles are 4J6, and the clip is in the 2nd position (second from the top)

Going to re-set up the carbs and if the weather holds give it a go later today.
Title: Re: Racer Resurrection
Post by: bsracer on May 12, 2019, 01:18:05 PM
I tried a 4J6 needle out at Willow last month.

200 main
35 pilot
4J6 with the clip in the top groove

Too rich off throttle (3/4 to WO) and bike would bog

went to a 190 main and 30 pilot with no real difference

went to a 4J15 needle which is leaner with clip in the bottom groove and a 25 pilot with the screw turned in to about a 1/4 turn out

I was running a 4DH7 needle prior which is leaner still with clip in the bottom groove.

I use to run 4D20 needles which are really fat (lean) but the clips for those are bigger diameter for the relief in the slides I use and the needle would be raised a bit.

paul
Title: Re: Racer Resurrection
Post by: SR-175 on May 20, 2019, 07:23:09 AM
Hi Paul,

Could you take a pic of the various needles you have.

In the attached pic, the one on the left is a 4J5, the one on the right has no markings. It came as part of a VM22 repair kit I bought for a Kawasaki A1.

I am using VM-22's off a Kawasaki A1 250.

Thanks .. ray
Title: Re: Racer Resurrection
Post by: SR-175 on May 21, 2019, 10:25:32 AM
Hi Paul, Al,

After digging through parts here I found a few other needles to compare. It seems the needles in the Kawasaki A1 250 carb kits are close too the 4J6's.

Note the main needle jet - the centre hole that needle jet slides in is smaller than the 2.5 mm diameter of the needles ??...

ray

Title: Re: Racer Resurrection
Post by: al_pritchard on May 21, 2019, 10:49:06 AM
Hi Ray

I was wondering what needle came with my rebuild kit. Guess it's a 4J6.

Was not particularly happy with the quality of the kit, overall. Some of the jets still had burs from machining in them. Decided to only use the gasket and put the rest of the shelf.

In the image below (click image for larger view) is the needle from the Kawasaki A1 kit I got. Next to a 4DH7, 4F15, and a 4J11. That 4J11 looks so short - no wonder it's so much richer than the others.


(https://live.staticflickr.com/65535/47110676014_5b176f2673_z.jpg) (https://flic.kr/p/2eM1wEJ)
Title: Re: Racer Resurrection
Post by: vinny g on May 21, 2019, 04:53:44 PM
Hi Al. From memory I ran 4D3/4 needles in N size jet holders/needle jet. You can normally fine tune on the clip but certainly you won't need much richer (thinner) I'd look for around a 4D3 in a N4 holder. Incredibly important to get this there or thereabouts as you can change main jet all you want...it won't make a difference unless you're close with needle/jet combo. When I ran 22mm's I used slot head jets.. 110-130. These are diametric.. (100 is 1mm) With 28mm's I run 200-210-220 hex head. These are flow rated.

Quite a while since I ran 22mm's but I've probably got it written down somewhere and will dig it out. Certainly though...N size needle jet.

Cheers, Vince
Title: Re: Racer Resurrection
Post by: SR-175 on May 22, 2019, 02:04:48 AM
Hi Al .... all,

It's a pity the kits are not made a bit better and marked. Even a note in the bag would help ? We reproduced these to blah, blah, spec ...

Yes, found burrs & swarf. The air screw & spring measured up ok ??.... and the gasket.

A can of worms has been opened up on what needle jet to use ?

ray
Title: Re: Racer Resurrection
Post by: bsracer on May 24, 2019, 11:25:29 AM
I'll try and get some pics of the needles I have in the next day or two.


paul
Title: Re: Racer Resurrection
Post by: BRT-GTR on May 25, 2019, 08:08:18 AM
          Here's another tuning guide I found useful when setting up the GTO.  Again aimed at the Kawa triples but they use similar Mikuni carbs to our Bridgestones. Lots of stuff you will already know but has some good basic info on which way to go with jet/needle sizes . Also warns against the use of non Mikuni overhaul kits as Al/Ray point out.
             https://www.3cyl.com/mraxl/manuals/carbtune/carbtune.htm (https://www.3cyl.com/mraxl/manuals/carbtune/carbtune.htm)

          See the section on ''Effect of jetting variables'' near top and the tables right at the bottom which show dimensions of various series 4 needles and needle jet sizes. Might help to identify those unmarked needles although would require measuring to a 1000th of a mm!!
        Hope this helps, a can of worms indeed.                                               Brian.
Title: Re: Racer Resurrection
Post by: SR-175 on May 26, 2019, 03:18:48 AM
Hi Brian,

Very helpful lead !!.... thanks ... ray
Title: Re: Racer Resurrection
Post by: al_pritchard on June 04, 2019, 09:15:32 AM

And it's alive. No, it's not Déjà vu. If you are on the Bridgestone Facebook group you may have already seen this. But I thought I should upload it, and record the carb settings, and next steps.

Set Up
Pilot Jet: 20
Main Jet: 230
Air Screw: 1/2 turns out
Float: 25mm
Fule: 112 octane / VP C12
Oil: 28:1 / Castor 927

Did't do any carb tuning yet. Just wanted to get the first heat cycle in. A couple of notes, and things to do. She doesn't idle yet - not unexpected. I didn't take any time to start to work that out. She also stumbles pretty hard as you open the throttle.

I suspect as I start to get the idle set, it will help the 1/8 open throttle stumble. If I understand the tuning it's a combination of the height of the throttle valve and the needle jet.

And thats for that link Brian. It's helping me better understand how the carb works, and how to go about tuning it in.

Click image to view video
(https://live.staticflickr.com/31337/47996233886_17e9ea5b3d_z.jpg) (https://flic.kr/p/2g8gfaU)
Title: Re: Racer Resurrection
Post by: BRT-GTR on June 04, 2019, 02:41:22 PM
            Congratulations on getting her running.   Here's how I went about getting the carbs right.
         Start at the bottom (idle) and work up the range to top end (main jet) with tuning. At 1/8 throttle she is on the top end of the pilot circuit.
             Suggest winding the idle screws up to raise the slides to a point where she will idle. Then adjust the airscrews, to give highest idle speed. Do one pot at a time, removing plug from other pot but ground the plug of the disabled pot on the cylinder head to avoid coil damage. Bear in mind this is a race tuned engine, it may not idle like a swiss swatch !!
   
           Ideally Mikuni say airscrew should be between 1-2 turns open. Less than 1 turn - pilot jet too small, more than 2 turns - pilot jet too big.  After adjustments you need to back off the idle screws equal amounts to give required idle speed.
             If a cylinder doesn't respond to the airscrew, the screw may have been overtightened at some time expanding its seat in the carb body (quite common in my experience). Not much you can do about this. With a relatively high idle speed the adjustment may be outside the range of the pilot circuits in which case set the best, reliable idle you can achieve.
              Once you are happy with the idle, move up the range . I wouldn't worry too much about the slide cutout at this stage, the factory went for a rich setting (small cutout), it may be OK. Come back to it if you can't get rid of the stumble. 
             Needle clip position/needle size/needle jet are the next items to play with, good luck.
Title: Re: Racer Resurrection
Post by: SR-175 on June 17, 2019, 10:33:45 AM
Hi Al,

You can also toss the air screw into the bin. After closer inspection and trying to use it I have found the originals to be better. The tip diameter is not the same by about 0.15 mm.
Title: Re: Racer Resurrection
Post by: al_pritchard on July 08, 2019, 03:57:02 PM
Yea, I didn't use air screw ether. Total crap!


Spent a little more time with her over the long holiday weekend. The goal was to get her idling, and take a quick run around he block

Got her running, and idling well enough - more on this below. And a good heat cycle in the engine.

But I couldn't get her to go anywhere. The minute you started to let out the clutch, she died. No matter how hi you held the RPMs, the moment you put a load onto engine she bogged out and died.

Back up on the bench. A quick pressure test told the story. 45lb of compression! Thats all she can muster from each cylinder. Pulling the heads you can see the oil drops outside the o-ring. So at least that explains why she can't move under her own power.

I think I cut the o-ring grove to deep, or to wide for the o-ring. So I'm going to take a little more off the head, and see if I can get her to give me something a lot better on a compression test.

The leak down test didn't show a problem. I guess because the leak down was about 4 or 5 lb. and the o-rings are holding at least 45lb.

Would be interested in what others are seeing from a pressure test.


(https://live.staticflickr.com/65535/48234599596_cab78714df_z.jpg) (https://flic.kr/p/2gujVZw)

(https://live.staticflickr.com/65535/48234599801_650ef9ed9b_z.jpg) (https://flic.kr/p/2gujW44)
Title: Re: Racer Resurrection
Post by: al_pritchard on August 30, 2019, 05:45:18 PM


So, I am at a complete loss. Any thoughts would be welcome.

Got a new - to me - set of heads in the other day. With the plan to cut them down and run stock head gaskets.

Since  was going to run a stock head gasket, I cut the heads a little more than the last set. These come out at 7.1cc. I figure the head gasket is good for 0.2 or more.

Buttoned up the engine, and gave her a good push. Fired right up, and fiddled with the idle a little. Once she was warm, she had no problem revving up. But she still won't make power. Tested with the engine warm, and I only get about 90 lb of presser. I am at a complete loss.

Top End
Ring Gap: 0.015" / 0.38mm
Deck Heigh: 0.040" / 1.01mm
Head Volume: 7.1cc
Base Gasket: 0.031" / 0.79mm
Head Gasket: 0.039" / 1.0mm
Head bolts torqued to 140 in lb.

*The head gasket crushes down to about 0.024" / 0.60mm


Stock 11.3cc on top
Cut 7.1cc on bottom

(https://live.staticflickr.com/65535/48649792456_b9cfeebc95_z.jpg) (https://flic.kr/p/2h81Un7)

NOS Head Gaskets - Thanks Richard!
(https://live.staticflickr.com/65535/48649792546_f014283c83_z.jpg) (https://flic.kr/p/2h81UoE)
Title: Re: Racer Resurrection
Post by: BRT-GTR on August 31, 2019, 07:02:24 AM
   Al,
        Initial thoughts,   
     Use annealed copper head gaskets, more up to the job, much better seal than alloy, and may allow reduction in head nut torque reducing distortion.  Your head nut torque seems low, what is BS standard figure ? haven't checked.
        Bog/lack of power may be due to weak mixture, try 1) turn in airscrews 1/4 turn at a time and test 2) if airscrews less than 1 turn out go to next bigger pilots 3) raise jet needles. Does she bog then go or bog then die. I found if airscrew was too far out with smaller pilots , she would bog on takeoff. Are plugs wet or dry after a test.
        90 lb pressure, seems low, not sure, rings need to bed in? piston clearance? Seems to be a noticeable visual difference on opposite sides in piston land clearance on left pot, bottom photo but could be camera parallax error or shadow. What's your compression ratio with new heads.                                                                         Brian.
Title: Re: Racer Resurrection
Post by: bsracer on September 02, 2019, 12:23:21 PM
Where is the clip position on the needles? And what needles do you have in the carbs? This is how mine first ran until we went to an extreme to find it was too rich. If I remember the mixture screws were barley cracked. You may have to put the clip in the top groove depending on the needle. 4D4 or 4D20 are fat taper. You may also want to drop to a 210 or 200 main to start. Are the discs cut 10 and 10?

paul
Title: Re: Racer Resurrection
Post by: al_pritchard on September 03, 2019, 08:53:31 AM
Hey Brian,

The deck heights match cylinder to cylinder. In the photo above the "left" (right in the photo) cylinder has the head gasket on, and the other doesn't. Don't know the exact compression ratio with the new heads. I'll assume it is similar to the old heads. Old heads were cut to 8cc, and were set up for an o-ring. The new heads are cut to 7.1, and use a stock head gasket. I'm assuming the

Uncorrected Compression Ratio: 13:1
Trapped Compression Ratio: 7:1

Going to start over with tuning, beginning with the air screw as you suggest above.

Hey Paul,

The carbs are currently:

Needle: 4F15 - clip in the 2nd position (from the top)
Pilot: 25
Main: 220
Fuel: 28:1
Timing: 2mm / 20°

Going to fiddle with it a little more this afternoon. I'll update with any progress.
Title: Re: Racer Resurrection
Post by: BRT-GTR on September 04, 2019, 08:37:19 AM
    Hi Al,
    We may be at cross purposes here, calculating your potential max cylinder pressure, I get 154psi but actual figure will be lower. 90psi suggests something is wrong. On the bottom photo, left cylinder,  there seems to be a much bigger cyl/piston gap on one side of piston but maybe camera or shadow/reflection.
   Good luck with the tuning, there's a lot of variables to play (Fiddle  ;D) with. I've been fiddling with my carbs for months. I have seen another tuning article which suggests getting the pilot jet and main jet settings ( that assumes she will pull through the  mid range)  sorted first because they have little or no effect on mid range running. Then play with the needle clip position and/or needle jet  size.                                                            Brian.
Title: Re: Racer Resurrection
Post by: bsracer on September 05, 2019, 11:00:22 AM
My bike is at work so I'll look at the carb settings later today. If the 4DH7 is the leanest needle you have, I would try that with the clip in the top groove. Try a 20 or 22.5 pilot, and put in 200 main jets if you have them. I would turn the mixture screws all the way in and just crack them open between a 1/8-1/4 turn. If you get it running and idling you may have to turn in the mixture screws in to get it to rev freely.

paul
Title: Re: Racer Resurrection
Post by: bsracer on September 11, 2019, 12:04:13 PM
I looked at my carb settings. I guess I tried some different things and didn't record them. I have the following:

4f15 needle
25 pilot
190 main
24/1 fuel mixture.

I had the clip in the bottom position and the mixture screw was farther out than I can remember. It was running rich last time out but I had also just reamed out a set of needle jets. My carbs are different than yours with a mix of jets from a few different carbs. I run 2.0 fuel valves as a replacement to the 1.5 stock ones that come in the carbs. I also swapped the float bowls with the external main jet type to some from a more modern 65cc mx bike with the large bottom hex screw access. I use the needle jets from these as well because they have the plastic shield around the main to keep down frothing. These carbs also have the neoprene black floats instead of the brass ones in the SR carbs. I've rattled more than a few of those apart.

paul

p.s. we'll see how it goes at Barber
Title: Re: Racer Resurrection
Post by: al_pritchard on October 05, 2019, 09:52:54 AM
I think you called it Brian. Unfortunately.

Tore down the top end to double check, and sure enough it's not to spec. Not even close. When I sent the cylinders off to Millennium for Nickel plating, we settled on a 0.002" clearance between piston and cylinder. I included the Wiseco pistons with the cylinders so they could be used for measuring the proper bore size. And everything came back in exceptional condition. Except as it turns out the cylinder bore size - are cylinders like people, expanding slightly over time?  ;D

Looks like what I actually have is 0.015" piston to cylinder clearance.
Bore: 1.9685"
Piston: 1.9535"

Rookie mistake, I ASSuMEd that the parts would be within speck. And it looks like they are not. I think my assumption was reinforced by what I thought was the correct ring gap. Such a learning curve...

Wiseco ring gap recommendations look like: Bore Size in inches x 0.005".

My ring gap with a feeler gage measures at 0.016". Looks like it should be closer to 0.009"

Time to jump on a call with Millennium.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 14, 2019, 12:52:15 PM
So I had a good chat with Millennium yesterday. I really recommend them! They were amazingly supportive in trying to help me track down where the issue might be. And unbelievably patient in dealing with someone with out an engineering, or two stroke development background.

From Millenniums notes
1.9697" - Cylinder
1.9695" - Piston

I don't have the best calipers - simple digital ones. But if I set it to 1.9695", I can ever so gently slide it down the bore.

The problem comes with the piston size. They have 1.9695 in their notes, but I get  1.9550" on my caliper. Giving us a piston to cylinder clearance of 0.0147 (about the 0.015" above)

I'll get them back on the phone later this afternoon. Hopefully they have a note with the serial, or part number for the piston I sent in. Otherwise, this is going to be a costly mistake.


By the way the measurement I get for the RM cylinder is 1.9550"
Title: Re: Racer Resurrection
Post by: BRT-GTR on October 14, 2019, 03:49:28 PM
    Al,
         As you sent them the cylinders and pistons, I don't see how the fault can be anyone's but theirs. I assume you have fitted the same pistons to your engine.  I use digital calipers all the time and find them pretty accurate.
        Surprising but sometimes they just get it wrong. Have now tried to fit two sets of Renntec engine bars to my Kawasaki W800. First set, rear mount bolt hole was 10mm out of position, they admitted the jig was damaged. Second set, would have had to  force front mounts in by 10mm to get them to fit so back they went. They have gone quiet on me and are having to sourcing a similar bike to check if bars are correct. I await their findings !! Had to contact Managing Director before receiving any explanation from them, lesson :- complain to the top man.
                             Brian.
Title: Re: Racer Resurrection
Post by: vinny g on October 15, 2019, 04:19:56 PM
Hi Al.
 This is a carb setting issue, it's as simple as that. Any issues with primary compression would cause the opposite problem to the one you have....it wouldn't want to start but once running woud improve. I've had my race engines show 90psi with single ring pistons on the only time I've ever checked it. This was at a meeting where a fellow competitor with a 200 Yamaha had a test gauge and asked if he could compare the two bikes. From memory the Yam was around 135psi. At the time I said I wasn't that bothered by any reading as I knew the engine was perfect. Four wins over the Yamaha over the weekend just confirmed that.
 
  Paul called it: Go to extremes with carb settings until you see improvements and take that as a pointer. You'll be amazed at the difference changes can make, quite literally from unrideable to race winner. I think you're rich on the needle/needle jet. I'd be looking at 4D3/4 needle and an N series jet holder. Mess around all you want with main jet etc...you won't go anywhere until that combination, on a small discvalve engine, is near perfect.

Remember: over standard you now have bigger carbs, inlet ports,disc valve timing and an exhaust system calling for fuel.

Lastly, don't give up. I started exactly where you are now and after a season of pushing and cursing sorted it in an hour. Experience is hard earned.

 All the best, Vince
Title: Re: Racer Resurrection
Post by: al_pritchard on October 15, 2019, 07:42:22 PM
UPDATED THE POST ABOVE TO CORSS OUT SOME BAD MEASUREMENTS

Imperial measurements now have Paul, and Vince in the lead for what is going on. Sorry Brian.

Thanks for the encouragement Vince, I'm not giving up yet. Loving the learning curve.

The measurements from Millennium are 100%. It's the nut holding the caliper that's off. Im my case it was HOW I was measuring the piston. So a little lesson for those playing along at home. When measuring a piston you do it from about 2/3 down from the top. I learned this, and a lot about thermal expansion today. :-)

(https://live.staticflickr.com/65535/48906075991_2a2230c573_z.jpg) (https://flic.kr/p/2hvEqwK)

(https://live.staticflickr.com/65535/48905556163_cb5f65a5ae_z.jpg) (https://flic.kr/p/2hvBL1c)

Smallest needle I have is a #4D8. And it doesn't look like JetsAreUs has anything smaller. So I'll try that as a start - just because I love to hear her run. And go on the hunt for a #4D3.
Title: Re: Racer Resurrection
Post by: SR-175 on October 16, 2019, 05:03:01 AM
Hi Al,

I have one #4D3 needle. Maybe someone else here has another ?

I doubt I have another but will have a rummage one more time to be sure.

ray
Title: Re: Racer Resurrection
Post by: vinny g on October 16, 2019, 12:55:52 PM
 I'll look through what parts I have as I no longer run 22mm carbs. I know I have a pair of 4D8 needles that, I'd guess, you would want to run in a N4 ish needle jet holder. I think you're too rich on the main jet also but until needle/needle jet is correct it won't matter too much. I'd think 190/195 is about right as a starter. If the needle jets you have, or can obtain, take the round slot head jet then I'm going for a 110.

Interestingly, I still run the same sort of combination in 28mm carbs but from the 5 series.
Title: Re: Racer Resurrection
Post by: al_pritchard on October 16, 2019, 07:07:50 PM
What is the series of the VM22 Needle Jet?

It’s stamped 132 then the Mikuni square and O-0 under it. But JersAreUs doesn't have a 132 series.

I can't find a reference to a 132 series any ware. It looks close to a 175 or 176. But that is the case, it looks like an N-0 is not available.

(https://live.staticflickr.com/65535/48913849567_cb091187cc_z.jpg) (https://flic.kr/p/2hwmgkV)

(https://live.staticflickr.com/65535/48913120073_235c275e36_z.jpg) (https://flic.kr/p/2hwhwur)
Title: Re: Racer Resurrection
Post by: bsracer on October 17, 2019, 12:53:33 PM
I just took those needle jets out of my jet box because I'm not using that type. I'd look for them and see what I have. I thought I had O-0 had maybe O-6. Similar problems at Barber this year. Hot and humid. Went from a  190 main down to a 160 and was still too rich.


paul
Title: Re: Racer Resurrection
Post by: bsracer on November 09, 2019, 11:04:45 AM
I finally found those jets and they are 132 O-6's


paul
Title: Re: Racer Resurrection
Post by: al_pritchard on November 12, 2019, 06:02:07 PM
Before the temperatures plunged, I drug the bike out yesterday. Wanted to test the 170 Jet, and have one more tries before it was on to fix all the little things I'm not happy with over the winter.

As part of documenting, and double checking everything before trying to start again. I found a problem... Seems when I set the timing last, I must have bumped something as I was frighteningly off. It was way out - and by way out like in the single digit degree BTDC. It was a scant 0.007 BTDC.

So it's no wonder it has no power delivery, and was so exceedingly rich. It never had the opportunity to burn the fuel before it flung it out the exhaust. Was basically acting like a big self propelled fuel pump.

Needless to say I'm a bit embarrassed. But for future builders, and amateur engine tuners. Triple check the timing!

Put the 20 pilot, and 200 main back in. Opened the air screw up 3/4 turn. And pushed as fast as I could. BANG, GROWLE! (Not quite that fast, it actually took a couple tries. But it was cool so...)

So with that we go into the winter with the big problem solved. It runs, and makes power.
Title: Re: Racer Resurrection
Post by: bsracer on November 14, 2019, 10:12:40 AM
Glad to see you got it figures out! I've got a mountain of work to get done for next season. Still can't believe AHRMA got Laguna Seca in February!!

paul
Title: Re: Racer Resurrection
Post by: SR-175 on November 15, 2019, 03:26:58 AM
Congrats Al !!!
Title: Re: Racer Resurrection
Post by: craig641 on November 26, 2019, 10:36:38 PM
Paul, 

Are the series 132 needle jets you're using the bleed type?  And do you remember where you found them?

Craig
Title: Re: Racer Resurrection
Post by: bsracer on November 27, 2019, 11:26:21 AM
Hey Craig.

I run different carbs at the moment so I'm not using those. They are the bleed type. The 132's come in the stock SR175 racer 22mm carbs and the Kawasaki A1 22mm carbs. I just found a similar 155 O-4 but I only have one and have no idea where I got it from.

paul

p.s. Did you get to run the bike with the new pipes yet? Laguna Seca in Feb!
Title: Re: Racer Resurrection
Post by: al_pritchard on February 01, 2020, 10:06:31 AM
A little mid winter update, as I sit in the shop watching the 2016 MotoGP season. Rossy has just checked out with a 2.8 second lead in the Spanish GP.


I'll get some more pictures later. But I made a new wiring harness. The deans connectors didn't feel secure, and I didn't like having all the connectors up under the tank. If I had to remove the engine, it would mean taking the seat, and tank off to un plug the Dyna S. So I redid everything, and used Deutsch connectors.

Old Harness
(https://live.staticflickr.com/65535/49472821476_c8eb16c2de.jpg) (https://flic.kr/p/2inK9dC)

New Wiring Diagram
(https://live.staticflickr.com/65535/49473118397_d96a065372.jpg) (https://flic.kr/p/2inLEtX)

With my earlier issue with timing, I made a tool to help hold the dial indicator. It may no the perfect, but its repeatable, and thats what matters. So now that I have a reputable process for measuring timing. I might have found another problem. The Dyna S rotors magnets are slightly off. Because I run the 1/2 engine speed dynamo, the rotor has 2 magnets. So when I set the timing at 0.071"/21° on magnet #1, the second magnet triggers at 0.081"/22° (just past 22° actually). Has anyone else experienced this?

(https://live.staticflickr.com/65535/49473043562_d462e6bcf7.jpg) (https://flic.kr/p/2inLheG)

And I started building a pit starter. Figured this would help me make friends in the paddock. More on this soon...

(https://live.staticflickr.com/65535/49233483906_66cca38b8a.jpg) (https://flic.kr/p/2i1AtuN)

Finally I acquired an early, new to me birth day present. Gloves!

(https://live.staticflickr.com/65535/49473043787_9308b2c48a.jpg)
 (https://flic.kr/p/2inLhiz)
Title: Re: Racer Resurrection
Post by: al_pritchard on June 17, 2020, 10:54:11 AM
Saving Weight

One positive of the lockdown. With all the extra time, I get to play on the lathe. Replacing a couple of heavy parts with aluminum.

With a savings of 4.67 un-sprung ounces
(https://live.staticflickr.com/65535/50016289801_a0949201b2.jpg) (https://flic.kr/p/2jcLyqa)
Title: Re: Racer Resurrection
Post by: OldSwartout on June 18, 2020, 07:51:40 AM
Good work! Always thinking of ways to make your bikes faster!   :D