Hi guys, I just picked up an 07 yz450f this past weekend. The guy i bought it from put a full akrapovic exhaust system on it and only rode it once with the new pipe and then it sat for a year and he sold it to me . He said that he never touched the jets so whatever is in it is what the stock set up is. I was hoping that someone on here has this exhaust system on their bike and they could share their jetting set up with me? It seems to run ok, there is a slight backfire on the downrev sometimes. I just fired it up at night and noticed the headers slightly glowing red. This scared the bejeezus out of me, but from searching around I guess its normal? I can't really see it glowing during the day. I am just running what looks like the stock air filter. There really are no other major mods to this bike other than the akrapovic exhaust. Any insight is greatly appreciated!