I changed out the carb on my 85 big red.When i started it up, it immediatley went to about 2000 rpms.I tried adusting pilot and idle screw nothing seems to affect it.Could the choke be stuck open?

 

Try the trottle cable it most likely will have a adjuster on one end for the idle. It may be where the cable and the carb meet.

 

I tried adjusting that and everything else i could.I checked out the choke and it looks good.I did fail to mention that the carb on there is off of a 85 trx250.

 

Does it backfire at all when you hit the gas? Pull the plug and check what color it is.

 

the throttle should have a little play. IF the cable has no play it will cause it to do that. If not the cable, reset the pilot screw to 2 1/4 turns out from being seated. Loosen idel screw all the way. Start vehicle, warm up adjust throttle, than pilot to stall, than back 1 turn on the pilot.