Fine-tune your GY6's final drive ratio with an NCY 14-tooth Counter Shaft Gear Wheel. Available in three driven gear options � 36, 37, or 38 teeth � this single gear change lets you shift the balance between top speed and off-the-line acceleration without splitting the cases. Fits both A-block (54mm) and B-block (57mm) GY6 engine families. ISO 9001 certified and made in Taiwan by NCY since 1997.
The stock GY6 150cc final drive is typically a 14?40 combination. Swapping the driven gear changes the ratio and shifts the power delivery:
Tip: Going to a lower tooth count (36T) raises top speed but means your engine will be spinning closer to its rev limit at speed. Pair with a big bore kit or performance exhaust to make the most of the taller ratio. If you just want a mild bump in top speed without sacrificing rideability, the 37T or 38T is the safer choice.
Fits GY6 157QMJ-based 125cc, 150cc, and 169cc engines with the following engine codes:
Don't see your engine code? If your engine code contains "QM" or "FM", this gear is likely compatible with your vehicle.
Performance upgrades are considered racing parts and are not covered by warranty. This product is intended for off-road use only and is not legal for use in California on pollution-controlled vehicles. Check local laws before installing.
California Prop 65 Warning: www.p65warnings.ca.gov
