I bought some aftermarket clutch friction plates and put I have them in my clutch group. The clutch doesn't work anymore. I can't put them in the gear when the engine is running.
I have resolved the problem with taking out one plate and now it's working well .
Can somebody tell me what the thickness is of the original plates?
Richard

Doesn't matter, replacement anything never fits! Just run it as it is and maybe when the new ones are bedded in you might be able to fit the extra one in.

How do you now when it's wrong or a wrong size.
I only like to know the real size of the original disk. The one I bought is 2.5mm.
Richard

Richard, original spec Ferodo rings were 3/32" thick. That's 2.38mm, so just a little less than your 2.5mm replacements. However, with all 8 rings installed that means your clutch is about 1mm too thick. Still not a lot, but enough to prevent the plates separating properly and cause the problems you describe. Other forum users have come across this problem and the accepted solution is as Douglas says, just run with 1 less ring and plate. Unless you normally drag around a heavily laden sidecar this should prove perfectly satisfactory - M20's were designed with sidecar usage in mind and running them solo gives the clutch an easy time.

I suppose you could try adding a hardened 1mm thick shim on the end of the clutch push rod, but that's just speculation and may (I can't work it out!) lead to clutch slip.

ChrisJ

Thanks Crish,
I have replace the disks without one disk and it's working perfect.
Regards, Richard.

Hi Richard...to be clear, you should remove 1 fibre and 1 steel plate and then readjust the clutch operating arm and cable to suit.
It will have no noticeable affect on clutch operation...Ian