How to Adjust the Mixture Ratio of a Scooter Carburetor?
1 Answers
First, prop up the vehicle, turn the air-fuel mixture screw clockwise until it bottoms out, then back it off by 1/2 turn. Rotate the idle screw clockwise until the spring beneath the idle screw is properly compressed (preferably around 4000 rpm). Start the engine, stop rotating the air-fuel mixture screw, and let the engine continue running. Slowly turn the idle screw counterclockwise to reduce the idle speed. After completing the above adjustments, while the engine is still running, quickly open and close the throttle by hand.