Splitting the 500 Engine.

[davegsm82]

I'll be taking the engine out of my bike tomorrow hopefully to replace the balance shaft which means splitting the crankcase halves.

I understand there is a special tool for holding the clutch, also I've seen one in the original manual for the actual process of splitting the cases. But I have to ask, can the operation be done without the tools?

I know the 251/301 engines can be teased apart with soft mallets gently beating on the halves very carefully, but the Rotax is a new beast to me. Can anyone advise?

Thanks, Dave.

[Srinath]

On some bikes you can wedge a penny between the crank gear and the clutch gear and take it off with impact driver.
Cool.
Srinath.

[DAVID THOMPSON]

watch the nuts and make sure you do not turn one the wrong way
i have not been in the rotax too deep but there may be some reverse threaded nuts in there
dave

[davegsm82]

I split it yesterday, not too bad all-in-all. Basically remove everything clutch-side, you can leave the alternator side stuff alone unless you need the gearbox or crank out.

Remove all the bolts from the alternator side, put a thin drift into 2 of the front and back bolt holes (all the way to the bottom), welly it with a soft mallet and the clutch side case will come away quite easily.

I'd recommend getting the clutch tool, I don't have one and it was a pig of a job getting the center nut undone. It's a standard thread by the way, not a left hander, there is a tab washer to contend with too.

Dave.