I was letting some friends ride my 2000 Bayou 220 this past weekend. Apparently they over- revved the machine and it jumped time. When pulling the valve inspection plate (front, I don't know if it is the intake or exhaust) the rocker arm was broke (cam side). I pulled the piece of metal out. The other rocker arm was not broke. Also, I inspect the timing marks. When the fly wheel mark is line the cam shaft sproket is not on its mark. My question, what other damage will i find? Are the valves bent now? How about the lower end of the motor? I'd appreciate any help, opinions or comments. Thanks!!

 

man that sucks. are they gonna pay for the damage? they should at least pay for a part of it

 

I found out what happened to my Bayou 220. It was not a over-revving problem or rider abuse. After going into the cylinder head, I found the the camshaft bearing and camshaft is held in place by a retaining plate. This plate is held in place by 2 phillip screws. One screw had backed out and fell down into the gearing in the crankcase. The other screw was loose and could be taken out by hand.

Either the retaining plate made the cam sprocket slide out of its pinned position or the screw wedging into the crankcase gears made the ATV jump time thus breaking my intake rocker arm. The intake valve, piston and cylinder head all look pretty good. I'm going to take the valve out and check the stem for straightness. I suspect everything will be good and I will only need to replace the rocker arms, camshaft retaining plate screws and head gasket.