Help, header pipe is too hot

I recently installed a Power Core IV Q muffler, and now my header is getting way too hot. I know it is normal for it to glow red, but mine is turning bright yellow/white with sparks flying off of it within 1 minute of starting the bike. The biggest problem with this is that the bike is already running a little rich, so I don't want to richen the mixture to cool things off. The muffler is new and does not seem restricted (at least restricted more than it should be). Anyone else notice this with this muffler?


'01 YZ426

'00 Harley Police Special(Got it for free, and I get paid to ride it!)

Why do you say its already running to rich?

I can't help you with this but I hope someone else has tried this as I have been considering one to replace my DSP spark arrestor because it is way too loud. I do have a buddy who put a new silencer on his XR 400 and the packing blew out and clogged the pipe (you couldn't see it) and made the bike run really bad. Good luck.

...because it is running rich. A little carbon/soot on the spark plug, no "popping", etc at any throttle setting whether accelorating or deccelorating, and any adjustments to the main jet, needle position, pilot jet or idle circuit to the rich side results in a poorer running engine. I'm thinking the muffler causes too much backpressure, raising exhaust temps.

[This message has been edited by tawood385 (edited October 13, 2001).]

white hot within 1 minute?wow that sounds scary,is there noticeably less exhaust coming from the muffler?maybe call up the manufacturer and ask or e-mail.only other thing is maybe a bad vacuum leak or something in the carb.usually white hot means a lean condition.i would swap original

muffler back on and compare.

I had a similar condition to this when I tore the rubber boot between carb and engine. It was sucking air. I'm much more careful now when turning carb to work on it.

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