Still working on the jetting. I put 26" 589's on at the same time. Did'nt seem to lose any power so that was good thing. I dont know that I would buy the QS1 again though. I saw a rinny with the regular HMF labor day weekend and it was not much louder than mine and seem to have more power. I put the 148 dyno jet in and I am thinking about going to the 146 to see if that does anything.