If you've never run a quick shifter before, I HIGHLY recommend it. This bike was fast before, even without any mods to it. I added more power via exhaust & ecm a while back and obviously that was an improvement. Today's efforts included new tires, 2015 compound pads up front, Vortex 44 tooth rear, DID chain and the quick shifter. This thing is absolutely BRUTAL on acceleration now. Full power upshifts = long wheelies. I was VERY hesitant to install the QS due to my fear of flipping or looping the bike. Yeah, well, it does wheelies pretty easy and shifting with the wheel up should save me some front tire wear.