Just picked up the new yfz450 yesterday and the header pipe glows bright red. i know most big 4 strokes glow al little but this thing GLOWS you can almost see through it. The whole pipe has already turned blue. Its backfiring alittle too. To me it sounds like its running lean. Other than that it runs great, very fast. If anyone else has seen this yet please reply, im going to run it by the dealer tomorrow. As soon as the aftermarket pipes, etc. are available its going to be rejetted anyway.

 

sounds like it is really running lean [img]i/expressions/face-icon-small-wink.gif[/img]

 

Check your plug as soon as possible and richen it up.

 

My neighbor / friend had the same issue when they brought theirs home. I guess the dealer re-jetted it but, sounds like this may be a hot running quad.

 

i have a 4 stroke and the headpipe doesn't glow at all. if it's bright red then there's definately someting wrong with it.

 

there's nothing wrong with your headpipe. while your motor may be running lean, its completely normal for the head pipe to glow red, especially when your sitting still. my yz426, my buddys yz450 and cr450 all do it. these motors put out a lot of power and make alot of heat.

 

there is nothing the matter with your quad at all. i have a yz250f and it glows bright red somtimes even blue when my bike is just sitting still idling. and my friends 2003 yz450f does the exact same thing. once you get going and the air gets flowing everything will go away.

 

If your headpipe is glowing red that means your exhaust valves are doing the same! Richen that thing up before you need to replace the valves. Anyone else that has a glowing headpipe should do the same. That is not normal. It is a sign something is wrong.

 

ridnwarrior, try starting your yfz up at night time and take a look at the header pipe where it comes off the motor. i bet you'll see a cherry red pipe within a few minutes of running.

 

what octane are you running?