How to Adjust the Carburetor Mixture Ratio to Richer or Leaner?

[DiBrooklyn]

First, check the tightness of the connections related to the carburetor to ensure normal air intake. Start the engine and let it warm up for 10 minutes to reach normal operating temperature. Tightening the carburetor mixture screw makes the mixture leaner, which means turning it clockwise. Loosening the carburetor mixture screw makes the mixture richer, which means turning it counterclockwise.

[LaRemington]

I adjusted the carburetor mixture ratio of my motorcycle myself. Locate the mixture screw on the side of the carburetor, which can be adjusted with a flat-head screwdriver. To enrich the mixture, turn the screw counterclockwise to allow more fuel into the cylinder, which gives more power when climbing hills, but too rich will cause black smoke and waste fuel. To lean the mixture, turn the screw clockwise to reduce the fuel amount, which does save fuel, but may lead to weak acceleration or even stalling. Adjust no more than half a turn each time, and remember to warm up the engine before making adjustments. After adjusting, take a short ride to test the acceleration—too rich or too lean can damage the engine. Beginners should note the original position and make gradual adjustments to avoid damaging the carburetor and needing to clean the nozzle.