Layshaft shims

Joined
Apr 29, 2009
Messages
1,203
Country flag
Measured the play after installing new roller bearing. .070, seems excessuve but everything is assembled correctly. 2 .030 shims?
 

concours

VIP MEMBER
Joined
Dec 29, 2011
Messages
4,243
Country flag
Gasket thickness? .020” (nominal)?
Kicker shaft internal bush shoulder ok? (not worn)
Is the layshaft original? Or newly purchased?

When you shim, remember that the rear iso shim I.D. must be opened up (I used a die grinder with a cylindrical stone) to clear the radius on the kicker shaft, otherwise you'll have a springy shim, which, then isn't a shim at all.
 
Last edited:

NickZ

VIP MEMBER
Joined
Oct 31, 2018
Messages
178
Country flag
Measured the play after installing new roller bearing. .070, seems excessuve but everything is assembled correctly. 2 .030 shims?
I had 0.060" end play after installing new lay shaft roller bearing.
There is debate as to whether shimming is necessary. However, I will say that with too much end play there is risk of kickstart pawl riding up over the top of the kickstart pawl plate. This can result in the kickstart lever getting stuck. Shimming kickstart shaft does not reduce that risk.
 

nortriubuell

VIP MEMBER
Joined
Aug 29, 2010
Messages
674
Country flag
I had 0.060" end play after installing new lay shaft roller bearing.
There is debate as to whether shimming is necessary. However, I will say that with too much end play there is risk of kickstart pawl riding up over the top of the kickstart pawl plate. This can result in the kickstart lever getting stuck. Shimming kickstart shaft does not reduce that risk.
I ended up shimming mine to .040" --- as the original .010" was just too tight. ( .010" is what classic bike experience shimmed it at when they rebuilt it.) I emailed Jack about my problems and he recommended loosening it up a bit. As stated before, some folks don't shim at all --- ever. However, having watched Jim Comstock's video, and I respect his work very much ... I believe some shimming is wise. But ... that .010" is too tight IMO.
 

Top