newbie to 4-stroke need help

Well I just picked up a new left over 2005 yz450f and I have only rode it around for 10-15min so far it seems like it is really really hot....exhaust header is turning blueish....is this all normal of a 4 stroke....how do I know for sure it isn't running to hot??? thanks for all your help guys.

The header turning blue is normal if you run the bike fairly hard. Most pro's can turn their pipe blue in a matter of laps but for the rest of us it can take a bit longer. My bike always feels very hot when riding compared to my old two-strokes, just normal for 4 strokes I believe since they create alot more heat than 2-strokers.

Also, it should be noted if you let the bike sit and run for more than 1-2 minutes the header will glow orange/red which is normal, air passing over the pipe when riding cools it so you won't see this but doesn't if you are standing still.

yea i just got a 06 crf450r and when i first started it up the pipe changed colors no big deal, they can overheat quick though if u just let it sit thier you will start to see coolant come out the overflow hose

Ok.....Thanks for all the help everyone....I just wanted to make sure I wasn't hurting my new baby at all....LOL

congrats on your new thumper, you will love it!

Yeah, 4 strokes rule man. Keep an eye on the coolant though. If it is loosing a lot while you are sitting after a short ride, you may need to rejet; but most likely, you're okay.

I hope so....it is alot different than a 2 stroke that I have always riden that is for sure

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