Glowing header?

Got my first 4 stroke bike a few weeks ago. Went and rode it in the snow a little while ago and came back at dark. At idle, my head pipe was glowing bright cherry red at the cylinder. I haven't checked the plug to see if it was lean or not. Should i bother? Or do the newer 4-strokes just run that hot? It is a 2001 yz426f with a 448 big bore and gytr exhaust. The previous owner claimed to have the carb re-jetted to be proper, but i have not verified this yet

Any input would be appreciated. I am trying to get all prepped and ready for riding season. So if i need to save up for some exhaust tape i will.

That's normal.

Yeah newer 4-strokes will have the header glowing when dark if left to idle for a few minutes. If it's as bright as I'm imagining the pilot jet may be a bit lean. But I wouldn't worry about it

 That is pretty normal. I have a plated '03WR and if I take a short run up the freeway it looks like there is a red light bulb glowing at the front of the engine. 

That's normal for a 426. You should only let it idle for about 45 to 60 seconds. Any longer than that, it will get too hot and start puking coolant. The bike needs to be pushing air through the radiator. I have the same bike, and had the same question.. someone told me radiator fans help, but I have never worried about it enough to try! Just keep that baby movin!!

Thanks guys. Just for shits and giggles ill pull the plug and see where thats at. Im just used to letting a machine idle when i sit there and talk. Now i have to get used to kicking. Lol. In the event that i dump the bike, will exhaust tape help me? Or will that cause more heating problems (by holding it in) and/or hold moisture and rust the pipe?

The only thing exhaust tape will truly do is prevent contact burns. 

Although exhaust pipe tape is good at keeping heat in the pipe and hence increasing exhaust gas flow (which is a good thing), I have read that it may require a change in setting to your fuel delivery. Since any performance gains you may see would be negligible, I find it not worth the effort or risk. I would love to hear from those that have actually used it and what effects they have experienced. Perhaps what I have read is wrong  :huh:

 

Perhaps what I have read is wrong  :huh:

 

It is.

 

There is no benefit to it apart from keeping the heat of the pipe away from other things, and with the whole engine out in the open, the only benefit from that is you won't burn your leg.

Although exhaust pipe tape is good at keeping heat in the pipe and hence increasing exhaust gas flow (which is a good thing), I have read that it may require a change in setting to your fuel delivery. Since any performance gains you may see would be negligible, I find it not worth the effort or risk. I would love to hear from those that have actually used it and what effects they have experienced. Perhaps what I have read is wrong :huh:

I do have experience with header wrap and it does effect at least the lower rpm's and air fuel ratios. Had to adjust an old Edelbrock carb on a YFZ 450 years ago because it went lean after the wrap. Didn't believe the manufacturer either but I witnessed it first hand.

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