still can't figure it out. so i'll try to list more symptoms hard to start, although with the clip moved up one it will niw start in 5-7 kicks instead of 20. smokes alot when fist started, may be normal don,t know. Hardly smokes at all when warm. Runs good for first 5 minutes then starts to run terrible. Make a loud snap backfire sound when it does start. bogs and can't get out of it's own way when warmed up. I have checked out everyones recommendations on carbs and jetting, but wouldn,t it run bad from the start if it was a fuel problem, plug is a dark brown. checked reeds there ok. mixing 40:1, ......Stumped? poor kid just got the bike and can't ride it. we test drove it and it was fine, but we diddn't ride it long enough for the prolems to kick in. Image a grown man taking avantage of a kid like that by screwing him with this bike. they made a trade and the guy already sold the bike my son traded him so he can't swao back, I appreciate anyone who can help us by taking time to figure it out, 2 strokes are all new to me I ride an xr.