Bridgestone Motorcycle Parts Discussion Board

Bridgestone Tech Talk => 175 & 200 Talk => Topic started by: TangoZulu on January 15, 2018, 04:28:50 PM

Title: Timing Marks?
Post by: TangoZulu on January 15, 2018, 04:28:50 PM
 So, time to disassemble the engine. But before I pull it apart, I want to know I'll be putting it together again so it will run: i.e. timed correctly. After pulling the right crankcase cover, I discover stamped dots on ALL of the gears. One on the Alternator, two on the fiber idler gear, one on the drive gear and two on the clutch gear ring. Woohoo. First of all, the pictures in the "Technical Handbook" look nothing like my gears (earlier model apparently. my '70 is model 16R.....) The dealer service letter says there are "no marks" on the idler gear. Not! So, if I spin it a bunch, I eventually wind up with a line up of dots that looks purposeful (photo). But is this correct? When they are lined up thus, the timing indentation on the flywheel is about an inch away from the "pin" (a shiny new wheel adjustor bolt) in the timing hole. So, when I put it together, how are all these timing dots supposed to look? What's the relevance to the timing mark on the flywheel? HELP!
Title: Re: Timing Marks?
Post by: BRT-GTR on January 16, 2018, 01:19:36 PM
                 See Page 23 of the aftermarket Clymer manual in the download section, mentions the fibre gear, it looks like your  timing marks are correctly lined up. I guess a previous owner has marked the fibre idler gear.
            The timing pin should drop into the timing hole when one of the points open, not necessarily exactly when the timing marks line up although it will be near as you have found. Check the points opening against the timing hole, you should find it is correct or very close (could need adjusting).
           Brian.
Title: Re: Timing Marks?
Post by: OldSwartout on January 19, 2018, 02:27:18 PM
I agree you've got it lined up right.  I don't see the marks on the clutch in your photo, you'll find the clutch gear also has marks on it to line up with the crankshaft gear and the fiber gear marks; however, they are usually somewhat difficult to see, not as obvious as the others.
Title: Re: Timing Marks?
Post by: TangoZulu on January 19, 2018, 07:38:25 PM
I figured the clutch marks (of which there were two) were irrelevant,
Title: Re: Timing Marks?
Post by: OldSwartout on January 20, 2018, 08:22:52 AM
They are as long as you're careful to get the alignment like you have in the photo.
Title: Re: Timing Marks?
Post by: BRT-GTR on January 20, 2018, 08:50:03 AM
            The marks on the fibre gear are also irrelevant, just easier to use them if they are there.
Also means you know the timing is right before you complete the engine, which was the basis of your original enquiry.
Title: Re: Timing Marks?
Post by: mybridgestones on March 01, 2018, 03:11:52 PM
Remember that some of the manuals cover the early type generator, so it may look different on your engine.
I always mark the dots with a felt pen to make it easier to identify when assembling the engine.
All the dots have to line up or ignition timing is impossible to achieve.
This is how it's supposed to look.
Stu