i rebiuilt my 4- wheeler and put a GYTR high compression pidston in it and also ported it. now it is overheating and idleing fast. i was just woundering what i need to do to it to fix it. i didnt re jet it or do anything else to it and i was wanting to know if i need to re jet it or what. could the timeing maybe be off, do i need i larger radiator, advance the timing, do i need a different exhaust system. any ideas would be helpful.

 

I would rejet it. It is probalely to lean causing it to run hot

 

Any time you increase the air flow in your machine, through porting/filter/pipe/anything changing the air flow you should reject. If you increase flow without adding more fuel it will run lean and run alot warmer than usual. You also risk burning holes in pistons or other damage.