On second thought...maybe I need to rejet or something after all. A buddy just told me that Im running very lean because the inside of my BUB slashcuts are clean as a whistle after 9 months of use and I have had a backfire 2-3 times starting it up, and my pipes make a distinct sound when I turn the bike off (hey is this normal?? It's not really a backfire, just sounds like one last THUMP in each pipe after I turn it off...one guy heard it at a gas station and said "uh-oh, better get that checked out"). Elevation: about 2100 feet here in the High-Desert.
I am not mechanically inclined so somebody give me some pointers if you would be so kind.
-How can I adjust it to make it run richer (Im SURE there's a thread, just didnt find it after a search, give me the title if you dont mind).
-Is that sound in the pipes anything to worry about?