troybilt
04-07-2008, 06:54 AM
Just got back from Little Sahara, and my buddy shelled the motor on his 86 ATC 250r. After tearing the motor apart, we discovered the piston skirt was broken... after digging deeper the tops of the left and right case was cracked too. Everything else seemed to be okay, no real play in the rod or crank bearings.
Does anyone know what causes the piston skirt to break? Would the shards from the piston skirt cause the cases to crack or would something else cause the cases to crack?
I read on here that there is a different length of piston bw. 86 and 87 pistons??? ...not sure there. We didn't do the motor work but the ATC the way it was, just noticed it was bored .020 over too.
Thanks for the help.
Does anyone know what causes the piston skirt to break? Would the shards from the piston skirt cause the cases to crack or would something else cause the cases to crack?
I read on here that there is a different length of piston bw. 86 and 87 pistons??? ...not sure there. We didn't do the motor work but the ATC the way it was, just noticed it was bored .020 over too.
Thanks for the help.