Product Description
Eliminate Spring Bind: Naraku Ball-Bearing Torque Spring Base
Optimize your CVT's shifting consistency with the Naraku Performance Torque Spring Base. This precision-engineered upgrade replaces the static factory spring seat with a high-performance ball-bearing assembly. By allowing the torque spring to pivot and twist freely as it compresses, this base eliminates "spring bind," resulting in smoother downshifting and more predictable acceleration out of corners.
Technical Performance Features
- Anti-Binding Ball Bearing System: Utilizes a captured bearing race that allows the spring to rotate independently of the pulley, reducing friction and internal stress.
- Improved Shift Response: By removing mechanical resistance, the rear pulley can react faster to throttle changes, keeping your engine in its optimal powerband.
- Universal 50cc Fitment: Specifically designed for the 139QMB engine platform and Piaggio/Gilera 50cc 2-stroke and 4-stroke transmissions.
- Low-Profile Design: At only 30mm in height, this base integrates seamlessly with both stock and performance torque springs without requiring modifications to the clutch bell.
Comprehensive Fitment Guide
This Naraku base (NK900.44) is compatible with a wide range of 50cc and 80cc scooters, including:
| Engine Platform | Compatible Brands |
|---|---|
| GY6 50cc (139QMB) | TaoTao, Wolf, Kymco, SYM, Lance, Bintelli |
| Piaggio 50cc | Vespa ET2/LX/S 50, Piaggio Typhoon/Liberty 50 |
| Euro 2-Stroke | Aprilia SR50, Derbi Bullet/Atlantis, Gilera Runner |
| Honda Models | Ruckus (Zoomer), Metro (CHF50) - (Verification Recommended) |
Technical Specifications
- SKU: 137-80
- Manufacturer MPN: NK900.44
- Overall Height: 30mm
- Includes: Spring base, ball bearings, and hardened bearing race
- Requirement: Must be used with high temp bearing grease
Pro-Tuning Note: This kit does not include a torque spring. For the ultimate performance setup, we recommend pairing this base with a Naraku or NCY 1000-1500 RPM Performance Spring to match your rider weight and terrain.