C: Clutch Clutch locking up

[Chris Launders]

Hi I'm seeking a little guidance, my clutch has come loose again and after cleaning and reassembling I cannot tighten the sleeve nut C20 without it locking the clutch solid, not C13 and the shoe assembly which is still free to rotate back and forth but C3, so it turns the engine over, I think it has been like this since I've had it but would like to fix it properly.
It seems to me this must be either the bushes in the chainwheel have flanges that are too thick or the back of C3 is worn, it is very shiny.
Are these the only possibilities.

 

[greg brillus]

Sounds like it........You could try machine a small amount off the inner face of the C3 or else remove the primary cover and the chain, chain wheel and crank sprocket assembly, and then trim the bushes..........Just for interests sake I think if the fit of the C3 on the mainshaft has any noticeable backlash on the spline, this will cause the C 20 nut to come loose again and again resulting in oil getting onto the clutch. You should be able to assemble the C3 through the chainwheel onto the mainshaft and tighten the C 20 nut fully and get at least 5 thou end float on the chainwheel itself. If this assembly is quite sloppy even if new bushes have been installed into the chainwheel hub, then the OD of the C3 is worn and should ideally be replaced. The problem with too much sloppiness in the chainwheel is it makes setting up the clutch quite difficult as every time you check for run-out on the outer pilot plate, something has changed and this is a pain.......Good luck with it all.

 

[Chris Launders]

Thanks Greg, I've just remembered I have what I think is a new C3 somewhere, I will try that in first, I would think it's hard to hold the C3 to machine that. I have put some medium grade Loctite on the threads and the wire is in one of the slots so I will use it for the moment but look for the other C3.

 

[stu spalding]

Hi Chris, it is possible, if the nut C20 is well tightened, for the sleeve part of C3 to bell out slightly and bind in the bushes PD22 and PD24. Cheers, Stu.

 

[Chris Launders]

Hi Stu, It's not doing that, it is definitely nipping endways, it's not getting tight as such before it locks up.