Fine-tune your launch performance and eliminate sluggish low-end takeoff with the genuine Polini Clutch Spring Tuning Set. Designed to fit original factory clutches on 50cc scooters, this complete tuning kit allows you to adjust your clutch engagement RPM to match modified exhausts, big bore cylinders, or sport CVT setups�ensuring your engine revs directly into its ideal powerband before sending power to the rear wheel.
This tuning spring kit is built for standard OEM 2-shoe and 3-shoe clutches across 50cc 2-stroke and 4-stroke platforms:
Clutch Nut Verification: This spring kit fits stock/OEM clutch assemblies with an M28 thread holding nut and 39mm rear pulley socket. It will not fit oversized 107mm or 110mm aftermarket racing clutches.
Mechanic's Tip: Use a proper clutch nut tool to safely remove the 39mm central nut. When installing, use needle-nose pliers or a spring hook to fully seat the hooks through the clutch shoe holes. Verify all three shoes retract evenly before reinstalling.
California Prop 65 Warning
