Got an 06 450 and the thing runs great. No popping, hesitation...nothing. But the head pipe is seriously purple. I've had a 99, 01 yz426, an 03 crf450 and none of them were like this. I am a 35 plus (very soon to be 40) and not a rever but I do hit some upper R's. Going to get some head temperatures this week with an infrared gage. The jetting is stock, never over heated... any harm in running it???? What jets Should I change if it runs good?