Piston skirt shattering

[Pistonkiller97]

Hi guys, I was riding my 02 blaster the other day and it seized up, so as normal Took it home to find the piston skirts have shattered and gone into the crank, so removed the piston cleaned out the whole crank housing and the crank was moving freely again, (vitos +3 crank) everything seemed ok, 5 days later a new standard piston arrived so put him in costing me 45 quid making sure arrows facing exhaust port etc etc, replaced barrel and head had more compression than usual everything sounded okay. So gone to start home started on second kick and ran for 20 seconds if that on idle by its self, after that I heard a metallic noise like what happened the first time and I've gone to turn it of and as I have it's shattered again and locked up. This after about 35 second running? So taken the head of again to find the exhaust port side shattered again! This is now 45 quid down the drain, could there be something doing this? The barrel was not scored in any way just piston shrapnel everywhere? I was thinking maybe my con rod is bent making it go back up on a angle causing it to shatter ? Would really appreciate a reply many thanks

 

[Awk08]

you're piston to cylinder clearence is beyond specs.
it must be bored to fit the next size piston,
do not keep throwing the same size piston into a worn cylinder or it will continue to shatter

 

[Blaner]

you're piston to cylinder clearence is beyond specs.
it must be bored to fit the next size piston,
do not keep throwing the same size piston into a worn cylinder or it will continue to shatter

Indeed. Do some proper measuring up. Also, flushing out the crank case after a failure is a terrible idea. It is simply not enough to "free it up" those bearings need to be 100% clean. This is not achievable without splitting the casings and removing the crankshaft to REPLACE the bearings.

 

[Blaaster]

x 2 .