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Can someone please explain to me why my header is GLOWING?

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first off dont tell me "this is normal" or "they all do that" because frankly that is a load of crap! my bike has NEVER had the "normal" problem or whatever people want to call it. my header literally gets BRIGHT red, not just red, think of the brightest red you can and thats my header. it looks like it is about to melt off! anyways, i raced all last year and never had this problem come up but when i went to put the bike away for storage last year. i was running the gas out of the carb and the header started glowing and burning my radiator hoses so i shut it off....FAST! i thought maybe it was just running super lean because i was draining the gas. i took the bike out today and worked on it, put gas in it and started like 3rd kick after sitting all winter :) i was soooooo pumped but then i started to smell something burning so i looked at my header and it wasnt red yet. i let it run for about 45 seconds more and what do you know........BRIGHT RED HEADER AGAIN! what the heck is wrong with my bike!? i dont think its jetting cuz they guy before me set everything up and its ran like a champ for the past two years but now all of a sudden this.......My only thought is my valves are off and need to be adjusted........what do you say/think? if the valves are off what would be the best thing to do, shim or just replace all together. i was looking into getting a new top end soon too so if the valves need to be done wouldnt it make sense to just do everything at once so it saves me labor cost. thanks for youe input and i really look forward to seeing what KJ790 has to say

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man i really don't know. has the weather recently changed where you live causing your jetting mixture and all that to change? i don't see how it could be your valves. How long do you sit and let it idle without riding it? BTW its not a stupid question, most people around here will just say "its normal, don't worry about it" but like you said i think their full of crap. you never see a factory bike with a glowing red header do you? anyway good luck!

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um well does the header glow when your riding it? I know im beating a dead horse but yeah your header will glow if your bike isnt moving. no big deal.

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Are you running it in a garage or another area without sunshine by any chance?

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Dude, your bike is one step from the junkyard. Being the kind soul that I am, I'll take that POS off your hands for $100, you pay shipping.

Seriously, your exhaust valves need adjustment. And yeah, they do glow when you sit still.

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it was in the garage but all the lights were on and its that bright that you could see it outside in the middle of a sunny day. ive had it in the garage before and its never done that. only these two times. the other thing is there is a very strong burning smell like putting plastic on a hot pipe, that bad smell and i cant tell you for a fact that it doesnt glow when i ride because i dont look at it when i ride. but ive had it for 2 years and its never done this. i was thinking the valves were not opening/closing at the right time and they are slightly open when the fuel combusts thus letting the hot burning fuel to enter the header and make it glow........is that crazy or could happen?

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Either you have no air flow or are out of coolant or have a cooling system problem or your jetting is lean.

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i though it might have to do with the exhaust valves but idk, i wanted an opinion first before i brought it down to a shop

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the thing is i hate messing with the carb and/or motor at all! ill do anything else but wont touch my valves/top end/carb/any of that stuff. i would how ever do a clutch or something like that

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Any 4 stroke engine can make the header glow red if it's running lean. This is also why you should never "run the gas out" because you can burn a valve. Yes, I know lot's of people do it, but lot's of people also have to rebuild their bikes in the spring because of a burn valve (ie ~ it starts hard).

In your case you may have done just that. You could also be lucky and just need a valve adjustment. If your exhaust valves are not closing all the way that too will make the exhaust glow red, as well as a lean (plugged up) carb.

Be prepared to pay for a reconditioned head.

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thing is bike didnt start hard at all.......gave it like 5-6 soft kits to get the gas through the carb and everything and then maybe 3 real kicks max and it fired right up and sounded good. i think its just the exhaust valves are out of shape......have actually never checked the valves in over 1 1/2 so that would be my guess now that i think of it. how long does shimming the valves last or should i just get all new vavles? would that also mean springs and seats?

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yup like i said i dont mess with my motor so it will prob be going to whatever shop can take it the quickest! 2 weeks til first race and i need to practice on it!

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prolly the exaust valves I would have it checked out before you do more damage

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and yes i know some peoples headers will glow but the difference between those and mine is that mine gets sooooo hot it actually burns the heat shield around my radiator hose and started to burn the hose itself. its going in the shop tomorrow to get the motor checked out

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To recap:

Your bike was running just fine last year, and you've installed bigger radiators and new hoses?

All 4 strokes will eventually run the headers to the glowing point, if the jetting is too lean, or, there's no airflow over the radiators! If possible, take your bike out and ride it for a few minutes, or blow air (with a carpet-drying fan) over the radiators when the bike is sitting still.

It sounds to me like you were letting the bike idle waayyy too long without moving ie: getting airflow over the radiators.

I would like to hear what the shop charges you and what the problem was.

Do you have the owners' manual for your bike??

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yes i have the owners manual and the shop said it would be 30-40 to check the valves and take about an hour. i needed the valves checked anyways and they are doing a pre-season run through of the bike. they also said it was one of the nicest looking bikes they have EVER worked on and it has all my practice plastics on it (looks alot nicer with my race plastic on). i keep the bike in ridiculously nice shape and everything. i know it needs front wheel bearings and all the other ones need to be grease, maybe steerinf stem bearings too. i only let it sit for maybe 2 mins (thats why im kinda "freakin out" about it because it is such a short time) and it ran perfect since i got it, well except when i blew my exhaust up :thumbsup:

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my wr450 did that in low light conditions.. freaked me out..i thinks its normal, unless u got carb problems. wr still running

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