After reading all the threads about the AIS removal mod, and hearing everyone rave about the vast improvements, I just found it hard to believe there would be that much difference in performance. I even read where people claimed it turned their wr 450 into a "whole new bike". I just spent about two hours installing the GYTR kit, and didn't even have to pull the carb off the bike. Well, gentleman....I BELIEVE. Every rave was right on the money! The first time I shifted into third, the front air lofted, and I damn near looped it. Felt like I was riding a bike from my old two stroke days! It started easier from a cold start, it idled perfectly, and smoothly, and all the backfiring was gone. I want to thank Arin for his excellent tutorial on the installation, and also a big thanks to Black Bones for guiding me to them. THIS FORUM WORKS! Thanks guys....looks like I found a home here. Now, I'm gonna go rotate my battery caps for good measure, LOL!