glowing head pipes

[bklyn400ex]

My friend has a brand new 400ex, he only rode it twice, and has a hard time starting, and yesterday when he got it started, we looked down at the header, and it was glowing a bright orange, i've never seen this on my 400, is this at all normal??? is not what can it be?

[crookedeyemoto-x]

I am not exactly sure, but I believe that is due to being too lean. Maybe someone else can shed som light on this.

[trxex]

it is normal to glow. i did a test, i over jetted my quad 400ex to see if glowing was normal .i put a 42 pilot,160 main ,clip all the way down on my stock 400 .it was excessivly rich and header still glowed.all my buddies headers glow ,i guess the stock header is thin metal .also read past post on fourm,other people header glows

[trxex]

bump

[bklyn400ex]

thanx bro, my friend was gettin worried

[BigThumper33]

a glowing header is a sign of being lean. My header and no one I ride with have ever glown. But my buddie's warrior header glows.....he put aftermarket mods(pipe/filter, etc) on his and never rejetted. I think its cause he is lean, his is a fmf header, so I has nothing to do with stock vs. aftermarket.

[2fastandfurious]

Ditto, lean! Did he try and mess with the carb yet?

[Nausty]

its just the new special glow in the dark exhausts;)

lol if he is having a hard time starting it and its cold out its pry lean. I'd rejet.

[trxex]

dident you guys read my post.i wayyyyy over jetted my stock 400 and headers still glowed .i know 5 or 6 400's that do the same .run your quad at 1/4 throttle at night not moving YOUR HEADER WILL GLOW!!!!!!!!!!!

[Martin Blair]

My 400 is all stock besides a few chassis mods, and my headpipe dont glow.

[trxex]

run your 400 tonight in the dark at 1/4 throttle,hold it there and dont move the quad "stand still" .when motor is warmed up it will glow.no doubt have not seen one that dont with stock header pipe

[Fluid400]

I just put on a custom ari box on my 2003 400EX adn that made my pipes glow as well. LEAN would be the correct reason for that. Ihave ordered my exhaust, Jet and Pilot, onced I change all of this it should go back to normal. Mine were bright red (glowing) as well

[joeroadking]

a bright red glow is not normal in my opionion, when I richened my jetting on the 440ex it reduced the glow to almost nothing where as before rejetting it looked like red hot steel !:rolleyes:

[NoWingNoPrayer]

im not tryin to be a smart *** or anything but i wouldent recomend running your 400ex not moving till the header glows. i got a 400 and 6 of my friends do too . my friend mikes glowed once at like 12 at night and he was doing donuts for way to long and he had a pipe no lid and a k&n with stock jetting. my guess would be to high of rpms and no air cooling it would make it glow, i mean its fire aint it! its gonna heat the metal up.

[jesshamner]

When I first got my t-4, I was reving it up and listening to it. I had a 160 main jet and it was glowing in broad day light. It is all stock engine and the airbox was in stock position.

[bklyn400ex]

my friends bike is totally stock, he bought it two weeks ago, and only rode it twice for around an hour at a time, and we noticed the glow, i'd guess because we were outside at 10:00pm and it was dark, and we just started it