We have an 07 CRF80F that when idling revs up and down and when under a load when you blip the throttle wants to die. What needs adjusting and where is the air/fule mix screw on this bikes carb?
Sounds like you need a bigger pilot jet or more turns out of the air screw. It should be on the left side of the carb if you were sitting on the bike. Sould be a smaller flat blade screw dirver. Turn it out a quarter turn at a time until it gets better (if it gets better). Test each quater turn out by bliping the throttle.
There is a fuel screw and it will be under the carb at the farthest forward point.
The adjustment on the left side of the carb is the idle adjustment. If memory serves me correctly the CRF50F has the idle on the left and the fuel screw on the right. Your 80 may be like that. Fuel screws make richer adjustments as they are turned out, air screws are the opposite.