Glowing exhaust header

I recently bought a '99 WR400. All stock. I have trail ridden a couple of times and ridden around the yard quite alot. While getting ready for a ride tommorrow, I was warming the engine to check my oil level in a dimly lit garage and noticed the exhaust pipe was glowing orange for the first 4-6 inches out of the head. Normal????? Or should I be looking to rebuild. All fluid levels good, water in radiator flowing.

Normal. Use the search button in the upper right and most of your questions will be answered by the Wizard, the wonderful wizard... :)

Normal! Every new WR/YZ rider seams to ask this question. The head pipe is real thin & the engine develops alot of heat. Not to worry, just the way it is. Wait till you get it real hot on a night ride and see it glowing bright red.

They're right bro... it is very normal...

a night ride in the middle of glamis... racing up and down oldmobile hill competition hill china wall... then sitting at the olds double just chillin watchin the people for a few min... my friend walks over and lights a cigarette off my glowing header... it was cherry red... everyone was tellin me YOUR BIKE RUNS TOO LEAN... im like can it its a 4 stroke thing u twin cylinder two smoke junkies...

I just went on a nite ride last nite and was wondering the same thing, the bike runs great so I wasn't to worried.

Thanks for asking the question.

I was wondering the same thing about my '99 WR400 and have seen the same thing on my '83 XT 550. I think Yamaha must retard the timing for the first 60 seconds after the bike is started causing the exhaust to heat up.

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