cracked sleeve diagnosis...

[jcs003]

i cracked a cylinder sleeve across the "skirt" on the exhaust side. the gasket blew out and started to leak.

what may of caused this? im assuming the gasket blew, drawing in more air creating a hot spot on the sleeve. this along with piston slap is what i think is the culprit.

any other thoughts?

[86 Quad R]

how old is the build and what bore is it on?

[jcs003]

Originally posted by 86 Quad R
how old is the build and what bore is it on?

about three years. its got a hot rods crank. the crank has horizontal movement but no vertical. so i assume the crank is still good.

[C-LEIGH RACING]

Piston slap could have started it or helped it, but normaly the piston will bust first if you have to much piston to cylinder bore clearance.

If you just put a new same size piston in a worn cylinder & didnt bore the cylinder to fit it, then that could have cracked it before the new piston had a chance to bust.
Neil

[Honda 250r 001]

how far was the cylinder bored out? around 69mm? that skirt gets purrrrrrty thin when you go past 68.50 bore...

[jcs003]

Originally posted by Honda 250r 001
how far was the cylinder bored out? around 69mm? that skirt gets purrrrrrty thin when you go past 68.50 bore...

i didnt even measure the bore. it needs a new sleeve and i dont remember what i put in there last. its always a good $500 to get er back together.