Recently my M20 was acting up a bit. I removed the primary cover to find that the cush nut had loosened. Tightened it back up and thought "that was an easy fix." When I went to take it out for a ride I shifted it into first gear, and while I was holding the clutch lever in it changed gear and hopped forward about a foot and stalled. Any ideas on what's going on before I start tearing into it? I adjusted the clutch arm so it's 90 degrees to the clutch rod. Obviously it's quite concerning when it shifts by itself and goes forward while holding the lever in! Any advice would be appreciated.
Thanks
James
James did you also check the clutch sleeve nut was tight? It's the one in the middle that the pushrod goes through. If this nut comes loose, the pushrod will push the complete clutch instead of just the clutch cover. Of course there might be another problem, but checking that nut is simple. Whatever, I think you need to remove the chaincase again. Ron
Thank you for your reply. Since I posted earlier I did take the chain case cover off again and removed the clutch dome. To my surprise, two studs and nuts broke off the clutch pressure plate. Inside the dome are witnesses marks of the studs tumbling around thus causing interference so the clutch could never be completed disengaged. So it's off to my engineer in the morning to have new studs welded back in. So in the end I had two problems, a loose cush nut and the broken studs.
Beat regards!
James
The studs were brazed in originally so any residual braze must be thoroughly removed before welding...The last time I repaired one I used countersunk screws that I turned the heads down on slightly...I countersunk the back of the pressure plate and then welded them in...Allow the plate to cool naturally and check that it's flat after everything is completed...Tweak if required!....Ian
Thank you Ian. That is the issue I've been thinking about. Makes good sense to countersink the back and use a tapered screw. Wondering if I should do all six at once so I don't have a repeat of this problem.
Regards,
James
I'd leave any sound screws in place...It's very rare that they fail in use, rather at the time they are done up..Fit a spring washer under each nut and resist the temptation to swing on the end of the spanner..A medium grade Loctite 'threadlock' would help in that regard as well...Ian
