Vintage Dirt Bike Q & A

My 75 CR125 clutch was slipping so I replaced the clutch friction disks. When I removed the six hex bolts that hold the clutch together I noticed that the bolt heads were worn as if they had been rubbing on the clutch actuator arm. Does anyone know how this could happen? The bolts, springs and washers are stock. The positions of the actuating arm is fixed by the clutch cover. The position of the six bolts is fixed by the axial position of the mainshaft. Can the mainshaft move to let the bolts hit the actuating arm??? Advice appreciated. Thanks. Mark

Were the bolts tight? If they were, maybe this was a problem sometime in the bike's past.
I doubt if the mainshaft would move enough to allow the clutch to rub. Probably wouldn't shift correctly. There'd have to be a transmission shim missing or some serious damage for that to happen.
If there's no noise while turning the transmission over by hand and disengaging the clutch, I'd say you're OK. You could put some blue marker dye on it to make sure its not rubbing.

Okay. I got to the bottom of it. What happened is that the big 22mm nut that holds the clutch on came loose and the clutch slid outboard a little so the six clutch bolts heads rubbed on the clutch actuator arm. The washer under the big nut has the tab to bend up to prevent the nut from turning. Over the last 30 years the clutch must have been taken off a few times and there isn't much left of the tab so it didn't stop the big nut from loosening. Unfortunately Honda doesn't sell the washer any more, at least in Canada they don't.

hi mdlafferty! Did you find a clutch lock washer yet? If not, I think I have a couple of those. You can pm me if you need one.