Exhaust Melting Plastics

So i just bought my 00 yz426f a month ago and I noticed that it is melting the plastics around the exhaust. I took off the number plate because it was melting within a minute of the bike running the first time I went out. I'm assuming I am runnning the carb way too rich or something. Could it possibly be the aftermarket FMF exhaust on there as well?

So i just bought my 00 yz426f a month ago and I noticed that it is melting the plastics around the exhaust. I took off the number plate because it was melting within a minute of the bike running the first time I went out. I'm assuming I am runnning the carb way too rich or something. Could it possibly be the aftermarket FMF exhaust on there as well?

They will melt plastics when you let them idle for any longer than a minute at a time. To prevent this on mine i went to napa and found some aluminum tape to cover the inside of my plate with and have not had the problem since. Also Rich would mean more fuel and cooler motor temps in most conditions and Lean would be less fuel and hotter temps.

Repack your muffler, shouldn't be that hot.

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