Hey guys I’m new on here and have a few questions for you. I bought an rm 125 I’m rebuilding. The guy said he rebuilt the engine but the compression was at 90. I popped the head off and found these things I’m questioning. The head looks like there is some pitting on it, and super light pitting on the piston. The ‘pitting on the piston is so light I can feel it. The cylinder looks good and there is no scoring or nicks. It fire right up and runs smooth but doesn’t have the compression I’m looking for. Do I need to get the head refinished? Should I replace the piston and rings? What should I do ?
Any input would be helpful. I was going to buy a new piston but it looks brand new and has very little play, it barely moves around in the cylinder, but does move slightly. The head is what worries me.
Any input would be helpful. I was going to buy a new piston but it looks brand new and has very little play, it barely moves around in the cylinder, but does move slightly. The head is what worries me.