what would cause my header to glow?

[polcat1p]

could it be my jetting? last time i rode it was 30 degrees warmer. then today i tried to start it and it flooded, so i pulled the plug then tried again. It started and i had it reved a little then i noticed the headers were glowing. Is that mean its lean? I have a 170 jet with a k&n with a full white bros pipe with 10 disks.

[Honda#4]

yea it's probably the jetting.

[PismoLocal]

ya its probably the jetting...............................













or nuclear radiation, one of the two. :blah:

[underpowered]

jetting. air is thinner when it is cold out so you need to richen up your jetting to make it run correctly. Just go up a size or two on the main or what i do is run my airbox lid in the winter and take it off for summer. works out pretty good. not exact but still works.

[hrc]

It could just be the quad 2 of my friends have yfz's and they have both done that since the day they brought them home.

[polcat1p]

its never done it before, but this is the first winter with pipe, filter, jet
i put the lid on tomarrow and see if it helps, then go from there.

[DieselBoy]

Air is denser when it is colder.

[Sleeper]

Originally posted by DieselBoy
Air is denser when it is colder.

I was going to say. Denser air equals leaner mixture. Thinner air makes you rich. So ya, you may be lean.


Sleeper

[midnight]

jetting,I had the same problem,so I re-jetted and it fixed the problem.Like underpowered said,go up a size or two and that should help

[Rico]

That would be from a lean mixture.

[Sleeper]

I guess that someone should mention that stock off the floor if you hold the engine at 2000 to 3000 rpms for more than 15 seconds or so the headers will glow and that's just normal.


Sleeper

[DieselBoy]

header glow is NOT normal...................................

[Joe400ex]

jetting

[Old Head]

Originally posted by DieselBoy
header glow is NOT normal...................................


Not normal on a 400 but seems to be a common occurance on the 450's

[Sleeper]

Originally posted by DieselBoy
header glow is NOT normal...................................


Go to your local dealer and take a bone stock 400ex and hold it at 3000 rpms for a while and the header will glow.


and this is what the man said.... "It started and i had it reved a little then i noticed the headers were glowing."

Now I don't know how long he held reved, but that will make them start to glow if you do it long enough. Now if it's glowing at an idle or when you just rev it for a couple seconds I'd say that's not normal.

Put in a new plug, take it for a ride and pull the plug and see what it looks like. Or if your popping on deceleration it's lean also.


Sleeper

[DieselBoy]

your muffler shouldnt be glowin or there's somethin wrong.... i would say its lean as crap. mine or any one of my friends bikes have never glowed, i would be concerned about the damage this could do to your piston.

http://www.mztech.fsnet.co.uk/images/pistons/piston3.jpg
This piston crown has an ash colour, which shows that the engine has run hot. The ash colour is actually piston material that has started to flash (melt) and turned to tiny flakes. If this engine was run any longer, it probably would've developed a hot spot and hole near the exhaust side and failed. The main causes of this problem are too lean carb jetting, too hot spark plug range, too far advanced ignition timing, too much compression for the fuel's octane, or a general overheating problem.

[Sleeper]

And if your muffler is glowing you must have bought a special glow in the dark muffler;)

Pull the plug and see if the electrode is turning white. If it is your lean.

If you re-jet put a new plug in and ride it for a while all warmed up then pull the plug and look. white = lean black buildup = rich.

[polcat1p]

I changed the plug, and put the air box lid on. It running like a champ now.

[crewworrior]

Hey dieselboy, i just bought a 6 degree advance key for my 400ex will i have to jet for that or will i be o.k. right now its jetted for my HMF slip-on with a k&n with the airbox lid on.im not sure of jet size.i bought the bike already jetted.any info will be appreciated.

[jordan_m6]

you shouldnt be glowing unless you are reving and not moving. when you break in a new cam your bike does not move and you have to keep the rpms over idle but without riding the bike. so your header will glow at the piont where the exh. port and header meet. but if it glows without reving you need to rejet.

when you rejet you need to make sure you plug is a light brown not only at the tip but also on the inside of the plug

[curious george]

yeah it is not taking enough air so the header glows and one of my freinds has a yfz and he says his header is supposed to glow. but i think that is what he gets for buying a yamahahahahahaha!

[Rico]

Originally posted by polcat1p
I changed the plug, and put the air box lid on. It running like a champ now.

removing the lid would cause a HUGE lean condition.. reason for header pipe glow. If you ever change the intake or exhaust you have to rejet..

[motochamp250]

my headers glow and i have been running it 4 a year and a half and have had no problems....lean is mean..... but they only glow when i get on it hard 4 a little while ...not all the time