I want to take this opportunity to thank Lowedog for developing the AIS removal kit for the '05 WR450. I have to admit, at first I was a little hesitant to install the kit cuz except for the typical backfiring on deceleration, my WR has been running flawlessly and I didn't want to take the chance of anything changing cuz of the kit. I've read all the threads on some of the problems people are having and I don't understand why. I've done all the free mods and have gone one size up on the starter, pilot, and main jets with the stock needle. For me, the JD kit was not necessary. I later installed the Power Now and the bike just rocks! The installation of AIS removal kit took me all of the two hours it said it would. I had trouble removing the fitting on the exhaust side of the cylinder and in my opinion, there is no way of installing the exhaust plug without moving the right side radiator out of the way. Well, since installing the kit, I have done two GP races in back to back weekends at Glen Helen in San Bernardino Ca. The second race was a non-stop 6 hour team race. For any of you who have done this race, you know how tough it is. They don't make the course easy just because its an endurance race. Both races took riders up and down all of the steep hills that this track is known for. The WR never missed a beat and I had absolutely no backfiring while decelerating. Except for the chain loosening up, the bike ran just as strong at the end as it did at the start. My fifteen year old son was one of my teammates and it was his first time riding my bike. During the race, he told me he must have tipped over about fifteen times, but when he did, the bike either didn't stall or one poke at the "e" button and he was on his way again. Sorry this thread is so long, but with friends that ride KTM's and all the attention that the Honda CRF450X is getting in the mags, I can't stop praising my WR. Everytime I wash it after a ride, I can't wait to get back on it again. TT is great and thanks again Lowedog!