93XR650L engine seized, anyone want to take a guess??

[Kyle_E]

I have a 93XR650L. I was riding it on the street today when the engine just seized bad enough to cause the chain to snap. No prior warning, engine noise, nothing. Just wump and there goes the chain. Oil is good and engine was running fine up until it just locked up. Anyone want to take an educated guess what the problem is, tranny, clutch, whatever. I haven't started to tear into it yet but it doesn't sound like the piston seized, more like something just broke inside the cases and locked up. Anyone have this happen before?? All educated guesses and not so educated guesses welcome. ???????

[captb]

Timing chain or valve? See if the engine will turn backwards and remove the spark plug see if you see anything with a small light, remove a valve cover and see if the cam moves (providing the engine will turn some), if the top end is good maybe remove the clutch cover, good luck

[XR6's_rule]

There is a number of things/problems that could have seized your bike. I know with XR600's, the first thing to wear is the cam chain. If the cam chain was rattling and really loose, it may have jumped, pushing a valve into the piston. Other than that it would be a one off for one of these bikes to just cease a piston or big-end bearing etc.