Various Questions

[Remington]

I wonder if the shim on my engine has been replaced, although behind the inner chaincase instead of in front, and behind the sprocket which would probably cause it to bind as I have installed another shim behind the sprocket (on the front of the inner chaincase) in accordance with the handbook instructions. Whoever put the drive side back together following the gearbox work appeared to know very little about lightweight, or even motorcycle, engines, and may have thought that he was re-assembling it correctly.

This may eventually explain the engine lock up when tightening the rotor nut although, as mentioned before, said piece of machinery had been secured with an airline (judging by the tightness) and the engine did, remarkably, still turn over although it seemed stiff on kick start.

Any ideas on this suggestion seeing as the breather assembly now appears to be intact?

It is a pity that the exploded diagrams do not show the 350cc engine as they are slightly different to the 250cc and this question of sprocket shims seems to be turning into a bit of a can of worms. Many thanks to all contributors so far for your help and suggestions, and at least some of us may eventually have correctly re-assembled engines if we can work out the likely shim positions (if any) when they originally left the factory.

[cbranni]

I may ramble a bit but you can blame the medication................the alternator rotor, sprocket and shim have nothing to do with the engine locking up, the drive side nut when tightened pulls the drive side axle towards the near side this tightens everything up, the nut against the alternator rotor against the sprocket against the shim against the ball bearing inner against the breather rotor and finally against roller bearing inner raceway which is up against the flywheel.
If everything is standard parts you can tighten this nut as tight as you like and it won't make any difference to how tight the crankshaft will turn, what will happen is the crankshaft moves towards the drive side now if the timing gear goes up against the timing side bush this will cause the engine to be tight to turn or even lock up the engine.
If breather rotor is missing or has been shortened this will cause the crankshaft to move too far to the drive side again this may cause the timing gear to foul on the bush.
If your engine shows any sign of tightening up when the drive side nut is tightened it needs pulling apart and checking for any previous butchery, I need to lie down now.........................

Colin

[Remington]

Many thanks, Colin.

Back to the drawing board for me. Hope you are still taking it easy............................

[Ozmadman]

If the timing gear goes up against the timing side bush this will cause the engine to be tight to turn or even lock up the engine.
If breather rotor is missing or has been shortened this will cause the crankshaft to move too far to the drive side again this may cause the timing gear to foul on the bush.
If your engine shows any sign of tightening up when the drive side nut is tightened it needs pulling apart and checking for any previous butchery.
Colin

Thanks Colin for he benefit of your experience, I hadn't considered that fact that the timing gear could foul the casing or timing bush at the other end, presuming that the flywheel would hit the casing on the drive side before that happened? But as you say an engine strip is the only way to find out for sure, I am glad I did that with mine!!

keep well

Paul

[Ozmadman]

Success with the sprocket!!! see "my engine work" thread page 8 thanks all for your assistance and suggestions

Paul