At first when I rode my new 06 it poped, the lean condition, yeah yeah...well now I moved up north, and it's a lot cooler up here, but I havent got to ride my bike yet because the plug is fouled and I now have time to work on it today. I called up my local shop/dealer and asked if they sell jets for the carb (Burned suggested a 48 pilot jet, leave all the others the same), he said I need to take my old jet out and then bring it for size comparisions. Can't I just tell him its a 06 YZ450F w/ Keihin carb, and I need a 48 pilot for it? First time Im going to tear into the engine on my 450 (well, carb/engine area). I hear it's a lot harder to get to the jets on this one. What is the best, easiest way you guys found to get to the carb without ripping everything out? And should I go with a 48, or since it's cooler now, should I go to a 47 or something? Isn't the stocker a 45? or 42? If I go too rich, is there another way I can lean it up without changing the jet, vise versa with too lean? Also, one other question while Im out in town, should I be worried about the chain guide thing hitting the swingarm? I can put some silicon I have (caulk silicon, same stuff) on if I need to, but Im just unsure exactly where it needs to go, and how much, is there anything else that needs to be put on with the silicon? Thanks A LOT for the help guys.