Cota 248 To A 348

[arbguy]

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

[bigshineybike]

• Not being very good at measuring the open casings, I approached this job by assembling the gearbox tightly with all bolts done up and gaskets in place. measuring the endfloat on the shafts is (in my opinion) easier and more positive than the process described in the Clymer manual. I made up my own spacers from brass shim.
  
• Does that make sence?
  
• 
  

[arbguy]

Thanks very much,

It makes perfect sense and will be a whole lot more positive than my current approach.

I'll not get to it for another week or so but will report back.

How did you measure the end float on the complete g/box - I've got decent verniers and I'm sure an old dti guage, they should be okay shouldn't they?

Thanks again.