What would prevent the clutch from disengaging? My 1977 XR75 was working fine about a year ago when I pulled the engine to restore the body. The engine sat, untouched, in my shed. The only thing I did to the motor/transmission was draining the oil. Fast forward to today, when I got it all back together. In neutral the wheel spins freely, as would be expected. In gear, the transmission engages like normal, but will not disengage when I pull the clutch lever. I have tightened it as far as it will go, almost to the point I can hardly pull it in with one hand. Is there some place I should look first? I have the book, but I know ZERO about how the transmission woks.