[rpt50]

Thanks for reminding me--I think I did see something about about these bikes pushing oil out a breather tube (into the airbox I assume) when run hard. I will check the airbox when I get a chance.

My bike unfortunately does see a lot of hard use. I needed to gear it down with a 15t so it could carry me (180lb) and tools (chainsaw, loppers, etc.) creeping along difficult trails without too much clutch slipping, but I still have to slip it a lot, which really builds up the engine heat. And with that gearing, it pretty much requires wide open throttle to keep up with traffic on the street.

I'll also check the plug at the next valve inspection, which I will probably do a little earlier than required since one was out of spec at the initial check. But since there is no visible smoke, I doubt it would show up on the plug at this point.

It probably would have been a good idea to do a compression check when the bike was new (or when I got it) for future reference, but it didn't occur to me at the time. Cool engine and throttle wide open is the normal procedure. I usually only do compression checks though when evaluating multi-cylinder engines (checking for consistency).