Im just getting the hang of doing slow 12's on my Raptor. Sometimes when I pop the clutch and get the front end up I wont give it enough gas trying not to flip it and it will stall and make a loud clank from the gears. Am I going to find little pieces of metal in my oil when I drain it?

 

Mine did that quite often too! Then it started doing it sometimes when I shut it off. Now it is doing it EVERY time I start it. See my current post on the subject. I would say that once in awhile is normal, but the more it happens, the more stress it is putting on your engine and the sooner something will give.

I am guessing that it has something to do with the engine stalling on the compression stroke. It doesn't quite make it all the way to the top, and doesn't fire, then the compression tries to push it back down, backwards. This, I'm GUESSING, is what puts the majority of stress on the 1-way bearing and the starter clutch.

This doesn't happen on a car engine because if it stalls when one cylinder is on the compression stroke, there are still other cylinders that have just fired and it keeps the crank moving forward.

The only fix I can think of for a single cylinder engine is some sort of mechanism in the engine that will let it rotate backward for some amount of revolution in this type of case. Maybe something that temporarily gives way if a certain amount of backwards pressure is applied. Or maybe some sort of shock absorbing device for the whole starting mechanism.

RR1

 

Like what racer1 said - it's probably the one-way taking the abuse when the engine kicks back on the stall. Sounds like your one-way could be on the way out if ya keep stalling it like that !?

I make it a point to start mine in neutral and put it in neutral before shutting done - much less clanking and drama !

 

Is it easy to ruin the 1-way bearing? Does it happen fast?

 

I couldnt answer that. One day it was working fine and the next its acting up. Mine sounds like crap. I cant wait for the lA designs to come out for now ill think ill go easy on it.