YZ450F Running Hot?

4 replies to this topic
  • 2weelz

Posted October 13, 2006 - 07:07 PM


Bike is a '03 YZ450F Supermoto Street Bike

I started the YZ and let it idle for a few like I always do. I went for a slow ride. I wasn't hammering it at all. All of the sudden, my head lights flicker and then go out. I still had my tail light. So, I ride a very short ways to a well lit parking lot. I got off the bike(still running) and noticed the header was glowing red. &%$#@!??? I turned it off and the header immediately quit glowing. I have been meaning to jet the carb which I think is running lean. It does pop when throttle is off. Would that cause the motor to run hot enough to light up the manifold? Is that considered overheating or just running hot in the right place? The oil is full as well as the coolant. Any suggestions?

  • TexN343

Posted October 13, 2006 - 07:50 PM


That is normal for the header to glow. Sounds like you do have a lean jetting and that can cause it to run hotter. If you are having fluid spit then you are having problems(IMHO). Aftermarket radiators are an easy fix. Check out fluidyne(sp?). Yeah that is spelled wrong for sure. Heard some people swear by 2twocool, a fluid you add to your oil.

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  • 2weelz

Posted October 13, 2006 - 09:21 PM


No problems with fluid leaks. I guess the header glow is normal for low speed operation. Everything seems as usual. I've only had the bike for a week...I guess I just never noticed it glowing. Now I have to figure out why the head light went out.

  • BergArabia

Posted October 14, 2006 - 03:45 AM


Yeah the glowing header is our number one favorite newbie post. And yes all of our YZ450s have glowing headers.

But what I am interested in is the lighting system that you have.
What kind of system is it? Baja Designs? etc. etc.
What components are included in your lighting system?
regulator? Wiring harness etc.

And I hope you get the bugs sorted out in which case I would be interested in what the problem is.

I am interested in all this because I am thinking of a lighting system for my YZ..

  • 2weelz

Posted October 14, 2006 - 01:01 PM


It's a Baja Designs external. It came with the bike so I didn't have to shell out the $450 or so to buy it. I'm not sure what all is included. I'm going to trace the wires and see if I can find the short or whatever it is. I'll probably just rewire it. It looks a little ghetto anyway.

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