Does anyone's stock exhaust glow red when riding? The reason I ask is that I've had my RZR since March and I just noticed it on my last ride. I've also been getting a few backfires on deceleration so I figured the two were due to a mixture problem and probably related to the way overdue for cleaning air filter. I've remedied the air filter have had no more backfiring (but also haven't had the chance to open it up good). But I still get the glowing red header pipe. It's a stock machine other than the foam UNI air filter. I've also noticed a marked decrease in fuel mileage but I'm pretty sure cleaning the air filter has taken care of that.