headers get red hot

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nick7338

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hi all i have just put a slip on exhaust on my 2007 fz1 and when i start the bike the 2 outside down pipes get red hot a glow the middle one stay normal colour could someone help me with this prob
 
Wow. I have seen that on older vehicles with bad catalytic converters (which your factory header has in it).... but on a newish bike? Odd that it's just two pipes, not all that get red. How does it run when this happens? Maybe you could gut out the cat, see if it persists? Strange that two are fine and the other two are glowing like they are extremely lean or something.
 
Do you have any other mods? Velocity stacks maybe? Any info on what you have (or previous owner) have done to the intake/exhaust would be helpful.
 
Were you riding it or just sitting there admiring it? If a bike just sits at idle the headers will glow, especially at night.

My Buell 1125R would glow cherry red after about 5 minutes of idle. I've not tired it with the FZ.

No worries....
 
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nick7338 said:
hi all i have just put a slip on exhaust on my 2007 fz1 and when i start the bike the 2 outside down pipes get red hot a glow the middle one stay normal colour could someone help me with this prob
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Scenarios like this are usually caused by unburned fuel entering the exhaust and reigniting. Causes are usually: too tight of exhaust valves, improper ignition timing, and/or too cold of a rating of spark plugs. Also the AIS can induce this since that is what it was designed to do, inject small amounts of air into the exhaust to reignite any leftover unburnt fuel. The AIS is like blowing on a small campfire to get it hotter. Go back and check the above items, have you done a valve adjustment recently, have you change the plugs recently, did you install a PC??? recently? If you have and everything checks out okay than ride the hell out of it and don’t touch the two outside pipes, I hear they are really hot!:icon_beer:
 
I would assume since the only thing he changed was the slip on and nothing else, she is running lean no? Happened with my YZF 450 dirt bike when I put a FMF on it. I had to richen it due to the new pipe. I would guess it's whats happening here too. Especially if he has not rode it a bit to allow the ECU to accomodate for the change in backpressure. I bet after a few miles she will calm down.
 
I was going to also suggest a severely lean mixture. I've never seen an exhaust (except in a bench test) glow red hot.

Unfortunately, I have certainly had many a brake rotor turn red hot due to a damaged caliper, but that's another topic.

You might want to bring it to a certified Dyno tuner or anyone who could do an oxygen test. What is your temp gauge reading when this is happening?

Hope this helps, and with all the info here, someone will certainly help figure it out.
 
Did you gut the cat when you did this slip-on? You may have damaged the O2 sensor and now it is confusing the ECU on the amount of fuel needed. That would be my first guess.
 
my pipes will glow after an extended idle . also my buddy`s gsxr 1,000 does the same . this is only visible at night and just before the fans kick in . M :noworries:
 
My FZ1 has never glowed but the FZ6 used to and that exhaust system was bone-stock. The pipes were impossible to keep shiny so I let them blue almost to black! The FZ1 is still shiny!
 
If my bike had been running "balls-to-the-wall" for a while I wouldn't be too concerned, but if your outside pipes are glowing cherry red after just a bit after start-up I'd get on it before you melt someting. Sounds to me like a really lean condition. but why just on 1&4 and not also 2&3?? Have you done any fueling changes? I can't believe a simple slip-on change without any other changes could cause this.
 
thanks for the replys to answer some question i have not gutted the cat and the only mods i have done in the twin high level ixil exhaust pipes i have studyed the bike on start up the glowing red outside pipes only seems to happen from cold when the choke is on as soon as the revs drop the pipes cool down i had the bike on tick over with th e fans on cos it had been running a while and the pipes were normal colour left bike a few hrs started it the choke kick in out side pipes glow red for a bit choke kicks out pipes go back to normal colour :doh2::doh2:
 
CrazyBiker said:
Variable Velocity stacks wouldn't make headers get red hot :D Definitely not unless you are running a F1 engine. Even the MotoGP bike headers don't get red hot.
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Just trying to figure out the dif in 1/4 and 2/3. He mentioned it's only on cold start up. The choke wouldn't cause a relative rich/lean situation in only two of the cylinders, would it?
 
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