Hello everyone,

I have been working on my 2004 klx300r for a very long time now. I am afraid that I have run into a problem and can't seem to find the issue. This may be a stupid question and there may be a simple solution to fix it but I can't seem to find it.
When starting my klx300r, I let it warm up for about 3 minutes (more or less), and very quickly, the exhaust near the header gets to about 320 degrees. Everything that I've been reading says that it is not normal for it to get this hot.
I am here asking what the problem may be and what I can do to fix it.

Thank you,
Chris

 

From what I'm reading that is actually cooler than I'd expect!

Exhaust gasses run upward of 1500°F or around 800°C inside the pipe, so that is relatively low. If the bike sits for around 10 minutes idling the exhaust may start to glow red, normal for single wall exhaust tubing. By the way, that heat is what turns chrome pipes blue and stainless pipes gold.

My SR500 had the head pipe glowing bright red around 12" up the pipe when I let it sit and warm up for about 15 minutes - in sub-freezing weather. In a block of riding it wasn't glowing. It takes air movement to cool the pipe, that or shut off the engine. Exhaust gasses from combustion are hot - simply very hot.

In other words, fire up the bike, don't let it warm for long periods of time. A minute is more than sufficient. Don't thrash it mercilessly immediately, but ride it reasonably for the rest of the warm up.

Nice to have a simple solution gained through new knowledge, right?

 

It is getting red hot tho and am still not sure if it should be. Thank you for the help.

 

Well, keep searching for something that isn't a problem if you so wish... Kind of Quixotic-esque.

As said, that is actually quite cold, when considering the exhaust gasses run two to three times that level. I've seen automobile dyno runs where headers glow...