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Rear sprocket stiff.

Posted: Sat Nov 04, 2017 8:44 am
by ove
Help needed please, when I torque down the rear sprocket/clutch it becomes very stiff to turn by hand even before I get anywhere near the correct torque figure. If I torque down the clutch basket only it all spins freely. Can't see any obvious places where it is catching. The shim is .75mm and that has signs of wear previously i.e. Shinny ring. Doesn't look like the endplate bolts are catching. The clutch basket sticks out further than the sprocket by about.4mm underneath as described in stickys first book.
It's a new gt casing and my used af road cassette clutch(no issue in last engine).
Help would be very much appreciated.

Cheers ove

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 10:32 am
by HxPaul
Firstly,are you calling the clutch spider"the clutch basket".When assembled,the clutch spider inside the bush and then inside the clutch bell "sprocket".The clutch spider should stick out of the bottom of the clutch bell "sprocket"by no more than 0.1mm,not the 4mm that you describe.

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 11:17 am
by ove
Thanks Paul yes and yes, the clutch spider and crown wheel(sprocket) yes the spider does stick out through the crown wheel by 0.4mm sorry I only put .4mm, so all is correct in that area.
Just put a flat straight edge across them and a 0.254mm feeler gauge is the maximum and that is very tight. Also re read sticky s book and it says ideally no more than 0.1mm!,!

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 1:05 pm
by HxPaul
Is the clutch bush too long?

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 2:31 pm
by ove
The bush is level with the crown wheel, both ends. I'm going to try a clutch spider shim to bring the gap down to under 0.1mm as you suggested.

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 4:23 pm
by HxPaul
As long as the spider is further out of the sprocket when assembled,then it shouldn't lock up.

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 4:39 pm
by garry inglis
I'm sure you don't fit the .75 shim with the af clutch I have one in and if I remember correctly mine did the same

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 5:55 pm
by ove
Thanks all, Gary if I take the clutch shim out it makes it worse. Hopefully problem solved, the crown wheel when torqued down is binding in the bloody endplate circlip. Take the circlip out and it spins freely. Obviously I can't leave that out, so I guess next step is to order a thicker clutch(1mm+1.2mm just in case) shim so hopefully this will lift the crown wheel off the circlip.
Do you think this will work?
I'll post results next week when I can get back in the shed.

Cheers ove

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 6:16 pm
by garry inglis
thats good i must have fit without and it locked up then put my shim in and worked

Re: Rear sprocket stiff.

Posted: Sat Nov 04, 2017 6:38 pm
by HxPaul
If you put a thicker shim(say 1mm difference) behind the clutch,put the same difference of thickness behind the front sprocket sleeve,that way you will keep the chain aligned.