Does the 6 spring clutch on my 56 B31 need a thrust bearing? I have quite a bit clutch wobble. None backwards and forwards but it rocks side to side. I have just dismantled it and there is no thrust washer there. Would this even prevent clutch wobble?
It has new bearings in. The two rows of caged small bearings. The wobble is worrying because when I run it with the primary case off it is quite noticeable. I don't want to run it now until I eliminate the wobble.
Thanks
David
Is this with the clutch engaged or released? On the 6 spring the chainwheel is free to move when the clutch is released as it acts as a friction plate. They can wobble about quite bit but it should all go solid when the clutch is engaged.
They all do that, once in use they strighten up.
Quote from: limeyrob on 08 Oct, 2025, 11:39 Is this with the clutch engaged or released? On the 6 spring the chainwheel is free to move when the clutch is released as it acts as a friction plate. They can wobble about quite bit but it should all go solid when the clutch is engaged.
It's when the clutch is released. To be honest I never really looked when the clutch was engaged. It just doesn't look right when it wobbles about and I think it can get noisy. There is no backwards and forwards movement, though. Perhaps I worry too much
David
They do clatter a bit when pulled in but the chainwheel is free floating as it has friction pads. Its not ideal but they are lasting 70 years plus so we can't be too hard on the design. Put the cover on then you can't see it : )
I have found that the inner clutch plate behind the chain wheel can cause excessive wobble and drag when the clutch is disengaged. To check, install the rear plate on the clutch sleeve, then install the bearing inner race, then the clutch driving plate housing, lock washer and nut. Tighten the nut a little. (Do not install the chain wheel or clutch plates).
Now with a dial gauge take a run out on the rear plate. Around 0.010 inches runout is good. 0.030 inches is excessive based on my clutch performance. To improve excessive run out, try indexing the rear plate on the clutch sleeve. If that doesn't improve the run out, try a different rear plate.
Let us know how you get along.
Jim
Thank you everyone for the replies.
Not entirely sure how but I have just put it back together. I think I had one of the two sets of clutch bearings the wrong way around. Anyway there appears to be little or no wobble on the clutch now
David