GY6 50cc (139QMB) Performance Clutch Set

Performance Clutch Set for GY6 50cc and 80cc Engines

This GY6 50cc performance clutch set is built for 139QMB-based engines and aims to lift your scooter's output. The kit includes a ventilated clutch bell that sheds heat more readily, which can help the clutch last longer. A 1500 RPM torque spring and 1000 RPM clutch springs are also included for sharper engagement and quicker response at lower speeds. It is a simple option among GY6 50cc scooter parts for a home installation.

Better Heat Handling

The vented clutch bell helps draw heat away during use, which matters for keeping performance steady on longer rides. Beyond supporting a longer service life, this design is meant to deliver consistent results across different riding conditions.

Stronger Engagement and Throttle Response

The 1500 RPM torque spring provides firmer clutch engagement, so the throttle feels more immediate. Paired with the 1000 RPM clutch springs, the setup is intended to improve low-speed power delivery, giving a smoother ride.

Specifications

• Clutch Bell Inner Diameter: 107mm
• Clutch Bell Outer Diameter: 115mm
• Clutch Inner Diameter: 12mm
• Bearing: 6901 RS
• Number of Splines: 22
• Inner Diameter (Peak to Peak): 11mm
• Inner Diameter (Valley to Valley): 12mm
• Includes: 1500 RPM torque spring, 1000 RPM clutch springs
• Fits: 139QMB-based 50cc and 80cc 4-stroke engines, including 139QMA, 1P39QMB and other QMA/QMB engines

Fitment

Fits:

• 139QMA engines
• 139QMB engines
• 1P39QMB engines
• 1P39QMA-2 engines
• YN139QMB engines
• JJ1P39QMB engines
• 139FMA-2 engines
• BD1P39QMB engines
• BN139QMB engines
• 147QMD engines
• Other QMA engines
• Other QMB engines

How to choose: Check the engine code stamped on the engine case against the list above. This set suits 50cc and 80cc 4-stroke engines that use a 22-spline clutch bell.

Shop more: GY6 50cc Scooter Parts (139QMB) · GY6 Scooter Parts · Scooter Clutches & Clutch Springs · Scooter Parts