M-Max help needed

[Lt Rascal]

My dads 2000 M-Max 700 keeps loosing the mag side cylinder. The piston drops a ring and chews up the head and cylinder wall. We have put one pison and a sleeve in the cyinder once every year for the last two years. Today it just went down again. It will go two dozen rides or so before going down. So I have a hard time beleaving its a crank seal. We jetted it up after the last one. But here we are again.

Any Ideas? I will try and post some pics when my wife gets home with the camera.

 

[spring snow hero]

pretty few things that keep killing the same hole......air leak, oil line fart.....lame carb....

hows the piston look?

 

[TRIPLESWILLNEVERDIE!]

If the cylinder has been sleeved the make sure the sleeve has not rotated in the cylinder. A local dude had the same problem and thats what it was. It would somehow rotate over time and the ring would catch in a port. Must have been bored with not enough press-fit tolerance.

 

[Yamamauler]

I agree with TRIPLES, it you had a bubble in the cooling or oil it would cook pretty quick.
Possible a tweaked reed?

Y

 

[0007]

Weird, 600 twin's used to do that all the time but the tripple is nearly bombproof
Sometimes it look's like a ring hook's but what can happen is detonation can act on the top ring with a shockwave, it can break away the ring land between the top and bottom ring, after that the ring get's cought in a port and it all bad after that
Lean is usually the cause of detonation, there should be other sign's