2T Crankshaft sideplay

[Ken Wilson]

I have just had the barrels off and replaced piston rings etc together with checking things in general and whilst re assembling the primary drive and checking the chain alignment I have noticed that there is about 0.7mm end movement on the shaft at the engine sprocket.
The engine was running well enough but play like this does not seem right!
Can anyone advise where this is coming from and does it mean a crankcase strip down?

[John Wakefield]

2T Crankshaft sideplay

I assume you mean end float on crank shaft. There should not be any as the crank is held tight in the drive side ball race when the engine spocket nut is tightened. (Is the nut tight) If there is end float it may be that the circlip holding the bearing in place in crankcase has come out of its groove & is allowing the bearing to move in its housing. If its that loose it needs to be investigated as it will wear the crank case housing. You could remove the engine sprocket & spacer & see if you can see where the movement is. If as I suspect the bearing IS moving in the crankcase you need to strip engine to investigate further.

[Ken Wilson]

Thanks John
You are having a busy time with me today!
The sprocket is tight and I will check out the bearing tomorrow but it looks like I will have split the crankcases
Thanks for your help
Ken