Hello all, 
I am looking for some expertise with rebuilding a Cota 348 gearbox. This bike started life as a 248 but now has a bigger cylinder and piston etc, but nothing has changed in the gearbox. 
My problem is achieving a good amount of end float on any of the shafts. No matter how many times I measure and alter the shims its either all play or nothing. 
Should there be a special shim/ thrust washer on the outer edge(pedal end) of the selector shaft? 
There is a little bit of distortion in the crank cases but the bolts seem to take it out. 
Does anyone recognise the problem? 
Thanks in anticipation, 
Arbguy