NCY BEARING SPRING SEAT - 50cc 139QMB, DIO, ELITE 50

Eliminate Spring Bind: NCY Performance Bearing Spring Seat

Upgrade your CVT's efficiency with the NCY Bearing Spring Seat. Standard spring seats allow the torque spring to twist and bind against the clutch pulleys, leading to inconsistent shifting and "dead spots" in acceleration. This NCY upgrade uses a dedicated ball-bearing track to allow the spring to rotate freely, ensuring smooth, linear power delivery.

Performance Benefits

• Consistent Shifting: Prevents the torque spring from binding, allowing for smoother "back-shifting" when climbing hills or decelerating.
• Reduced Friction: The integrated ball bearing race eliminates metal-on-metal torsion, extending the life of your torque spring.
• Improved Throttle Response: By allowing the CVT to transition through gear ratios without resistance, you get snappier acceleration out of corners.
• Universal Tuning: Compatible with both stock and aftermarket performance torque springs.

Technical Specifications

• Design: Needle/Ball Bearing sandwich plate.
• Construction: High-tensile steel races for maximum durability under high heat.
• Compatibility: Designed for 50cc 4-stroke (QMB139) and 2-stroke (Dio/Elite) clutch assemblies.

Confirmed Vehicle Fitment

This bearing seat is a direct fit for most 50cc scooters with a 107mm or smaller clutch diameter:

Mechanic's Note: This is one of the "secret" mods for the 139QMB engine. It makes a noticeable difference in how the bike reacts to throttle inputs, especially when paired with a 1000 RPM or 1500 RPM torque spring. Ensure the bearing is lightly greased with high-temp CVT grease during installation.