Fuel Jets, Air Jets, and Throttle Positions
Three circuits control the air: the air-screw, the throttle slide, and the air jet. Four circuits control the fuel: the pilot/slow jet, the spray-bar/needle jet, the jet needle, and the main jet. The different air and fuel circuits affect the carb jetting for the different throttle-opening positions, as follows:

• Closed to 1/8 throttleÑair screw and pilot/slow jet
• 1/8 to 1/4 throttleÑair-screw, pilot/slow jet, and throttle slide
• 1/4 to 1/2 throttleÑthrottle slide and jet needle
• 1/2 to full openÑjet needle, spray-bar/needle jet, main jet, and air jet