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MK 3 Chain alignment

Started by Clive, 24 Oct 2010 at 03:38

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I have always had a harsh feeling from the final drive at about 60 mph pulling hard ,not there going down hill. Have not long ago replaced all the bearings in the G/ Box  so i have been looking further down the drive train ? it appears the rear G/Box tubular spacers are not standard mine measure LH 2.513 and RH 0.865
The parts book i have gives four spacers for the LH side 2.365----2.375----2.386-- and 2.397 my next question is what should the RH standard spacer measure ,
Please could someone measure theirs and let me know and then i will have a starting point.


         Rather than just fitting the standard size spacers, I would remove the chain and lay a string along the side of the sprockets to check that both sprockets are correctly lined up, and then fit suitable spacers. Remember, these bikes have now had more than 60 years of, maybe, not so careful use - so the frame alignment may not be as it was when it left the factory!
       The harsh feeling could be caused by a problem with the drive shock absorber - take out the spring and reassemble to check whether the cam gets close to riding over the top (there are 2 lengths of splined sleeve available and you could have a mismatch). If it does, add a 1/16" spacer over the splined sleeve to restrict the travel, regrease the shock absorber and assemble. Make sure the through bolt is fully tightened (the whole assembly should be clamped solid with just the sprocket and cam able to move on the splined sleeve) and splitpin replaced. Roadtest to see if there is any improvement.


Thanks Eddie,
Will do, i know its out of line the chain is rubbing on the one side of the drive sprocket and the opposite side on the  wheel sprocket. will do the alignment as you suggest  and and make spacers to suit.  Also check out the shock absorber as well didnt know there there was different  components thanks for passing on this valuable info.