Guys, i have a 2002 sportsman 400 that starts and runs when you gently push the throttle, however when you push it as you would when normal riding it just stalls out. I’ve been through the carb and boots on both ends of the carb. replaced the cam and adjusted the the valves to .006. After doing these steps all is the same. starts and runs under lightly push on the throttle but when you hit it hard it just stalls and may even backfire.