Hey guys i just picked up a 04 yz450f yesterday. It was 1100 bucks and is in very good shape but needed a head gasket. The previous owner said it was extremly well maintaind and ran fantastic. I replaced the headgasket and the cylinder wall looked perfect inside. Im a diesel guy so im not very good with these little gas engines. i used the wrong timing mark on the flywheel the first time but have it fixed now. i cleaned the carb out and changed the oil and air filter. i couldnt kick start it at all so we pull started it and it would harly turn the wheel cause it has so much compression but it fired and it took a lot of throttle to keep it running. It had a lot of power but im used to utility atvs so not a real fair comparison. it would die instantly if i tried to idle so im not really sure what could be the problem.