DYNAMO Questions - Condensers Points etc.

[Romaine]

I am going to go through the point system and I am struggling with a few questions.

First I need to identify what I have - so I can order points and condensers.

I don't have a serial number- I cannot locate it.  see my original post here: http://bridgestonemotorcycleparts.com/index.php?topic=3232.msg16625#msg16625


I contacted the treasurers office (it has not been registered since 1994) and they told me the serial number is 16R29857

Here is a pic of the Dynamo..

BUT to me it looks like the pics "Before Serial 16G" - using the "Bridgestone Catalogue" page 8  "Dynamo Neutral Switch"

What should I order?

[BRT-GTR]

           The good news is, based on your photo, your points and condensers are interchangeable with those used on Kawasaki  KZ550/650 machines and maybe other Kawa models.  Just Google or look on Ebay. Make sure the clip that holds the felt cam pad, points the same way as yours, it was reversed on some Kawa models.

    Brian.

[dcr]

Check out BS Service Letter #BSG-0046 REVISED dated 6/1/67.

This 2 page document details the 3 different configurations of the 175 dynamos. It also has the various part numbers for condensers and points. The differences appear to be single lobe cam versus double lobe cam as well as the physical location of the points and condenser. 2 of the 3 configurations use the double condenser set up and the other one uses "split" or single condensers on the left and right.

I am certain you will understand the Service letter explanation a whole better than mine.

Dan

[Romaine]

Check out BS Service Letter #BSG-0046 REVISED dated 6/1/67.

This 2 page document details the 3 different configurations of the 175 dynamos. It also has the various part numbers for condensers and points. The differences appear to be single lobe cam versus double lobe cam as well as the physical location of the points and condenser. 2 of the 3 configurations use the double condenser set up and the other one uses "split" or single condensers on the left and right.

I am certain you will understand the Service letter explanation a whole better than mine.

Dan

Thank you Dan - this brings a bit more clarity to the issue.

It does look like the bottom pic on the Service Bulletin. This has a "double condenser" and the orientation is similar. If I understand you correctly - I believe I have a double lobed cam (flat on two sides of the center rotating rod)

Also -It would match my serial number identification above 16L.

I follow up with Richard to see if he has these.. If not I will check into a cross reference for the Kawasaki models  - Thanks for the tip Brian!

[dcr]

I ended up with all 3 types in various conditions and didn't really pay attention to the details of them at the time i took them apart. I threw the cam lobes in a bag as well as the points and condensers. I figured when it was time, I would take the best of the pieces to make 1 complete dynamo. When I noticed the condensers on one of them being separated, i grew suspicious. A little research turned up the Service Letter and the biggest surprise was the single and double cam lobe setup. Im sure that would have proven to be a HUGE issue had I used a single lobe where a double was required, or vice versa.

Moral of the story - don't ever assume anything on a BS bike is the same as that item on another BS bike.

[slawsonb]

This makes 350's seem very straightforward. I guess the devil really is in the details. 
...bert

[hmmmnz]

i have a spare double lobe cam, and points if you want them,
i got sent them by mistake instead of the single lobe stuff that i have,
just pay postage if you want them.
no good to me

[dcr]

This makes 350's seem very straightforward. I guess the devil really is in the details. 
...bert

Having rebuilt a 50 Sport, 100 Sport, 175DT and a 350GTR as well as completely disassembling a 90 Sport - Your dead on there Bert. In comparison to the others, i would say the 350 is pretty basic and simple.

[slawsonb]

Then it really is right up my alley!...lol
...bert

[Romaine]

i have a spare double lobe cam, and points if you want them,
i got sent them by mistake instead of the single lobe stuff that i have,
just pay postage if you want them.
no good to me

Hey that sounds like a plan - I will PM you shortly..  (The point part numbers are 1752-8001 LH and 1757-8001 RH correct?)

But first I need to verify what CAM I actually have as the catalogue states it is a "single lobe cam"..   

Just to be clear - the center rod that the points are touching is the CAM correct? If it has 2 flat spots its a double lobbed and if has one flat spot it is single lobbed correct?

Its hard for me to tell as my LH point isnt opening..

[Romaine]

Ok - I think I do have a single lobe cam upon further investigation..  as it spins the only time the RH breaker opens correlates with one high spot on the center rod..

Now I need to figure how to set the points.. I suppose I need both screws loose to adjust?

( I know what your all thinking - I already have one screw loose to be messing with a BS)

 

[hmmmnz]

You should have 2 screws on each point plate.
Rotate the engine until the point starts opening.
Loosen the 2 screws off on that sides points. Slide a 0.30mm feeler gauge into the gap and adjust it so the feeler guage just rubs on the gap. Then tighten the screws.
Rotate the engine and repeat for the other side.


If you are not sure if you have a single or double cam
You could pull out a spark plug and rotate the engine
If the cam does a full rotation to the cranks full rotation then you have a single lobe, 
If the cam only does half a rotation then you have a double lobed cam.

[BRT-GTR]

        Quote '' Rotate the engine until the point starts opening.''

   The points gap is set with the points fully open, not starting to open. I.E. The fibre cam follower must be sitting on the highest part of the cam lobe. Then adjust that points, base plate to give the required opening as described above.

    Brian.

[BRT-GTR]

          Following on from above, and in reply to your questions in Moonpup's 350 dynamo post, let's try and answer some of your queries.   'Get out clause'  - It is assumed that your bike has it's correct dynamo and has not been fitted with some hybrid arrangement in the past, it looks like it has not been messed with, all the screws are in great condition.

        You have correctly identified your dynamo as the final version used on the 175. Yours is the 1703-8002 (EN07). It has a single lobe cam and should rotate at engine speed.
   
        Although the points plate assembly looks and is identical to the 350 dynamo, the complete dynamos are not interchangeable. 1703-9000 (EN06) is fitted to the 350. The points cam is different and there may be other internal variations to give the correct ignition timing.

       The base plate, L&R points and double condenser are the same on both dynamos and have the same part numbers. It looks like your points cam could do with a good clean with fine sandpaper before setting or changing the points. Installing the condensers requires a basic knowledge of soldering.

       Romaine, it sounds like you are new to bikes and engines but, hey, we all have to start somewhere, well done for having a go.  Setting the points and dare I say it , the ignition timing , is quite critical on a two stroke engine. Over advanced  timing can cause the engine to run hot, resulting in engine failure  .  Do you have someone with experience who could look over your shoulder while you do this work. If not we are all here to help you.

  Good luck,  Brian.

[Romaine]

If you are not sure if you have a single or double cam
You could pull out a spark plug and rotate the engine
If the cam does a full rotation to the cranks full rotation then you have a single lobe, 
If the cam only does half a rotation then you have a double lobed cam.

Thank You!! - I really wasn't sure of that relationship - and verified this morning I do have a single lobe.

[Romaine]

         
       Although the points plate assembly looks and is identical to the 350 dynamo, the complete dynamos are not interchangeable. 1703-9000 (EN06) is fitted to the 350. The points cam is different and there may be other internal variations to give the correct ignition timing.

       The base plate, L&R points and double condenser are the same on both dynamos and have the same part numbers. It looks like your points cam could do with a good clean with fine sandpaper before setting or changing the points. Installing the condensers requires a basic knowledge of soldering.

       Romaine, it sounds like you are new to bikes and engines but, hey, we all have to start somewhere, well done for having a go.  Setting the points and dare I say it , the ignition timing , is quite critical on a two stroke engine. Over advanced  timing can cause the engine to run hot, resulting in engine failure  .  Do you have someone with experience who could look over your shoulder while you do this work. If not we are all here to help you.

  Good luck,  Brian.

Yes! Thanks Brian.

Now it all makes sense - every time I was looking up part numbers for points and condensers - I was getting 350 Dynamo parts - not HS175 - so I was a bit hesitant to order. The only real clear picture was in the service bulletin - which BTW isn't that clear -

I don't have a big brother to look over my shoulder -   but I do have this board thankfully. I have worked with points, coils, condensers attached to a mechanical distributor,   ( even the carburetor) on a 1979 Mazda RX7 but that was 27 years ago.. every car after that has been newer with computers..  (I am rebuilding a 1974 Fiat 124 Sport Coupe  - but that is a whole different cat)

 I have never really worked on any 2 cycle engines in really any capacity.  So I am taking this slow and asking questions.. 

Sad thing is I haven't even tried to turn her over yet..

[slawsonb]

We all started out with the need to learn, so keep asking and know that the answers will keep coming.
...bert