Sounds like the carb is plugged. Take the carb off, take it apart and thoroughly clean out all the passages with some carb. cleaner. Use compressed air to blow out the passages. Check the diaghram and be sure it is not torn or ripped. Make sure the pilot jet is not plugged. Be sure the fuel lines are not kinked or plugged.
As far as the track is concerned, check the primary clutch for a binding spring. Also check the fly weights and make sure the move freely and do not bind. Check the secondary clutch also and be sure the spring is not binding.
