I'm deciding to repair my Zongshen 140 that had the oil spinner nut come loose and destroy the clutch basket and crack the crankcase. Iv got a new crankcase now and I'm trying to assemble it but I can't get the gearbox to work smoothly once assembled.

I have zero clearance on the counter shaft, so it won't move in and out at all, and about .3-.5 movement on the primary shaft.

Seems the drum will only shift smoothly if I don't have the washer and bolt tight on the flywheel side. The drum needs to move toward clutch side to shift and being tight up against the other side of the case wont allow shifts.

Can someone tell me how much movement or clearance there should be on primary and counter shaft or what my issue here might be? My final primary shaft shim is .5mm thick. Iv gone over the diagram and there isn't any shims or washers or anything missing.