overheating

[snowmonster9]

i have a 2002 400ex after the bike has been running for about five minutes the pipes turn cherry red, i checked the oil ,full any answers?

[WHITE SEAT]

I know on my YFZ my header turns red after just 20 seconds of just running... If your 400EX is anything like my YFZ its normal...

Oh this should go in the 400EX section;)

[sly400ex]

Running way to lean

[Kickstarts-suck]

wrong section

check your plug probably lean

[Ripitupfilms]

OPEN FORUM he can post anything he wants...

[400exrider707]

Originally posted by WHITE SEAT
I know on my YFZ my header turns red after just 20 seconds of just running... If your 400EX is anything like my YFZ its normal...

Oh this should go in the 400EX section;)

Not normal... your lean.... check your jetting

You guys can search this to this is/was a very well debated and talked about topic.;)

[WHITE SEAT]

Originally posted by atvracer9m
OPEN FORUM he can post anything he wants...

Open forum, off-topic posting allowed. If you have a specific question about your ATV please post it to the appropriate forum! Keep it clean! ;)

400exrider707
I'm pretty sure I have my jetting perfect on the dot:p

[smr]

It's not normal. Either your jetting is off or you have carb problems.

[Rootar]

if your head pipe is glowing DONT ride or even start the bike until you put atleast 2 sizes bigger main jet, running that lean gets yuor EGTs way to high and that is bad itll ruin pistons if you continue to run it like that

[1fst400]

I dono guys. I know my 400 was jetted corectly at one point in its life. and the head pipe did glow.


take the plug out and look at it. or better yet take a picutre of it and poast it up.

[Honda#4]

you are waaayyyy lean!!! buy some bigger jets , i can help you find a staring point for jetting just give me all your motor mods and i'll tell you what you need to run.

As for the header glowing red, my header gets up to 275+ degrees and it does'nt even turn red, so my guess is that your lean thats all I can say.

[450rcrazy022692]

i had it happen to me, im 99% sure its your jetting, also what kind of pipe and stuff do you have and what kind of gas do you run?The reason why im askign that is i know 2 people that had glowing pipes by there exhaust have a TEC from yosh in it, and another one had there pipes glowing from running my race gas without a race engine. But in the end they jsut had to go up a jet or 2 do to those things.

[1fst400]

lets not jump to conclusions. what if he has a bone stock bike and its just doing it out of the blue for no reason.


lets hear some more info on what has been done to the bike and where it is run, elevation, and temp. and what the current jetting is.

[Kaleigh]

is it glowing when you idle or riding.. most the times it will glow when you are just idling.. I was told its normal for it to glow.. but if its glowing really bright then you have a problem..

what kind of lighting condition where you in when you noticed it.. most the times when it glows people dont notice it cause it bright and sunny out.. then when they go riding at night for the first time or so.. they notice the pipe glows a bit..

[400EXTRA]

re jet it