I have NEVER heard of filing piston rings. Where exactly would one apply the file without ruining them? Strange -- I would really check out that advice...
For a leak test, I believe the other member meant to check for intake/crankcase leaks. Moving the kickstarter and feeling the compression is not that test. There are two ways to check for leaks:
1) remove pipe and carb and plug everything up solid somehow. Put piston at BDC so the transfers are open and remove the spark plug and put a small amount of air pressure into the bore (you would need a spark plug hole tool that would include a pressure gauge And shrader valve on it. You put the pressure into the system and then see how fast it leaks out. Somewhere there should be specification for this leak rate -- I don't know what it is. This is a pretty big deal.
2) Instead of all that, button the whole bike up and start it. Set the idle best you can. Get a can of silicon spray and shoot around the connections between the carb and the engine, around the base gasket and under the mag cover (to check for a leak on that side main seal). If there is a leak the engine tone/speed will change while you are spraying in that area -- or the engine may just die. If there is no reaction to the spray then you are good to go. This should be done at idle when there is lots of vacuum downstream of the carb. Much easier than the above method.
So I finished installing the top end today. When I pump the kick start it's very tough and firm. No leaks as far as I can tell as of now. My friend noted me on something though, I never filed the piston rings, I wasn't even aware of such practice. Should I take the jug out and do them? I'd think they would come ready for installation since it all came together.
