1986-1988 Honda TRX 200SX Fourtrax Service Manual, Page 47Get this manual
FUEL SYSTEM
AIR SCREW ADJUSTMENT
NOTE The air screw is factory pre -setAdjustment is not necessary unless the carburetor is overhau led or new air screw is instal led
(1) AIR SCREW
CAUTION
Damage (0 (he air screw sea( will occur If (he airscrew is (ightened agains( (lie sear
Turn the air screw clockwise until it seats lightly and back it out' -1turnsThis is an initial setting prior to the final air screw adjsutmentWarm the engine up to operating temperature Stop the engine and connect tachometer Start the engine and adjust the idle speed with the throttle stop screw
IDLE SPEED: AOO 100 rpm
Turn the air screw clockwise until you hear the engine misses or decreases in speed, then counterclockwise unti the engine misses or decreases in speedCenter the air screw exactly between these two extreme positions Readjust the idle speed with the thrott le stop screw, if necessa ry