i have a 89 gs 500 with 15000 miles on it i am having problems with when i rev it up the rev is high an hangs there only way to get it down is with the carb screw of let out on the clutch a little in gear....also the slides on the carb right in side the airbox at idle one goes up and down alittle and the other one does not more is that the way it is to be ....whats wrong HELP