I am a newbie to the sport and just bought my first bike ('04 WR450) It is stock except for a JD jetting kit. As I was looking at the mods and looking at the bike, I cannot identify the AIS from the descriptions that I have read. I am starting to wonder if the previous owner removed it, if the 04 even had one, or if I am just not looking for the right thing. The youtube dirtbikevids conversion that is shown on a WR250 makes me think that mine must be gone since I can see none of the tubing coming off the engine. Any help is appreciated!