Running Hot and Lean

I have an 06' wr 450.It is running lean and hot.Im afraid the head pipe is going to start a fire.

Ive done most of the mods-

removed ais

jetted to 170 from 165

opened the air filter box

removed throttle stop

changed back sprocket to 51 tooth

white brothers pipe(e series).

I have not changed the fuel pin clip to the 4th clip yet.

would jetting to a 175 make it run richer?

the bike runs great and fast,just real hot (head pipe glowing in dark).

Is making the bike run richer my answer anyways or is there something else Im missing?

thanks for your time!

When is it getting hot? all fuel jets that have a higher number will make it richer ( less the leak jet ) but you have to make it richer wherever in the band she gets red hot in,

The "glowing headpipe" is a feature that all WR's have, no matter what the jetting. Search this thread and you'll understand. Putting a fatter main jet in it will not cool the headpipe enough to make it stop glowing. It will still glow at idle. If you're not boiling coolant regularly and it runs strong through the powerband and starts easy, I wouldn't change a thing.


I would say 1-2 for sure (hill climbing) havent really paid attention when riding straight aways.

:applause: Yeah man I have an 05 and I used to worry bout the cigarette lighter near my leg and all. I have been puttin mile after mile on this thing though and have found that as time goes on the pipe glows a little less. Guess you could say that the pipe turns. But I have not had any troubles out of the motor due to lean heat or whatever. Matter of worked out pretty good a couple weeks ago when a smoker buddy needed a light.

Had mine start a fire one time.

Went to the garage one cold winter day, as always I started it under choke after I got my boots on. While getting my helmet and gloves on I smelled something burning.

Went back to the bike and found a small bon fire of a bunch of high grass and debris that balled up under the head pipe guard. Quickly killed the engine and swatted it out with my gloves.

I must say that flames under the plastic gas tank are probably a bad thing.

It won't be the main jet causing it to get hot unless your on the power full time. If your pilot jet is less than a 48, try a 48. If it's the original 45, this is the cause of it. Only other reason is an air leak between the carby and cylinder. Your bike shouldn't run hot but the pipe will glow red if you idle it too long or speed is too slow.

Dont worry about your pipe glowing red, but like odonks said, dont start any fire with it either :applause:

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