my sons pw50 was running poorly, so I pulled the plug and it looked caked with a rust colored substance. I pulled the head and it looks like it detonated. I pulled the brand new piston and the bottom part is scored. Should I just order everything new ie... piston, head, rings, or could there be another issue to this. He ran it out of oil in the injector pump 3 weeks ago so I pulled the pump gear apart and now he runs premix 32:1, yamalube 2R. Is this an ok mix? Also I run half atf half marvel mystery in bottom end. any guidance would be greatly appreciated. Please no replys to go buy a new polini, ktm or cobra this is the class he races in we have other bikes.
