GY6 QMB139 50cc CVK Main Jet Set
Set Fits most Chinese Scooters.
Includes: 5 Main Jets #80 - #85 - #90 - #95 - #100
Easily Tune your Bike for OPTIMUM Power
Start VERY FAT, and then go leaner - to ensure no detonation
Carburetor jetting: You must set the carburetor jetting correctly by experiment. Put the main jet in, and run it full throttle long enough to get the plug colored. The best reading on a 4-stroke is a light tan, with perhaps some darkness around the edges. Some factory setting are so lean that they are bright white.
