08' CRF250R Red Hot Exhaust

On my 08' CRF250R, I recently had to replace a head gasket because water had gotten into the engine. I flushed all the water out & put a new head gasket. Which means I had to re-time the cam. It started on the first few kick. But starting then dying without me giving it a little throttle. After about 30 seconds of me giving it throttle, it started to run on its own. I was walking around the bike checking everything out, & notice my header pipe was bright cherry red (much brighter than in the picture). I instantly turned off the bike & did some research. I noticed that it is normal for this to happen. But most cases it stated that it could be seen at night. Where I was in mid day & it was cherry red. The engine seemed to be getting hotter than usual as well, I have all the oil & coolant in. Don't know what could be the problem. I really want to ride but I'm not sure if it's safe. Help please?ImageUploadedByThumper Talk1430575781.910558.jpg

Go buy a cheap temp gun from autozone or advance or napa or somewhere similar. Then measure the temp near the radiator cap. Its easier to notice the hot header when its low light or middle of the day. But anyway if you ride the bike for a while and bring it to operating temp check the water temp. If its normal then everything is fine

Damn, SON..... that pipe looks real hot!


Anyway, what caused the motor to leak coolant into the cylinder in the first place?  Was it running hot before?  Did you check to see if the head or deck is squared and if not, do you get the head resurfaced or the block decked before putting in a new gasket?


Did you check the thermostat?

Edited by Cute2strokeBoy

How long was it idling? That bike isn't made to sit and idle, so if you let it idle for 5 minutes straight it'd be hot as hell. What does it look like after a ride?

If it is getting hotter than it should it could be lean on the pilot jet or fuel screw. Or maybe an air lock in the cooling system.

Those bikes don't have a thermostat.

Edited by sjvmtb

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