piston

Hi all, I rebuilt my ‘79 CB750 and have been chasing low compression in cylinders 3&4. I pulled the engine and discovered catastrophic gouging to pistons 3&4 and the corresponding cylinder walls. All the piston rings are intact. Anyone have any idea what might have caused this...

Any tips or tricks? I just installed new piston rings and they're really giving me a hard time sliding into the cylinder jug

I have taken a 1973 cb750 motor apart. The previous own put new rings on but come to find out #2 rings are broken and scratched the piston wall. I have 2 extra sets of pistons the ring gap on extra sets are not the same as the ones in the motor. The pistons in the motor have larger gap? I...