i just bought a 421 cub with 4mil crank 5mm long rod, and cool head. got 22 domes, stock carbs, and stock reeds. running t5's. in the carbs i got 400 mains and 30 piolt. with needle set in the middle. not running right.. NEED HELP PLEASE!!! a stock banshee can spank me up olds. hill in glamis.. and after riding it for ten min it losses power and overheats...