Have an '07 450x and have obviously been out of the loop for a while. My last bike was a 250 2-stroke. Considering a pipe (possibly the WB E2) and jetting. Iam unsure about what to use for my elevation (around 325') and i ride woods / tight trails. Iam clueless but have read several posts on jetting but almost everything i' ve found starts around 1000'. any reccomendations are appreciated. by the way, what is the smog (AIS)? and should i modify it?