Universal Parts Torque Spring
Universal Parts Torque Spring
$20.16
Out of stock
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Product Details
Description
Universal Parts Torque Spring
Key Details
- 151-144
Specifications
- Overall Length: 97mm Width: 57mm Baja SC50, Kymco, Panterra, QMB139 50cc/49cc , Roketa, SUNL, Schwinn, Tank, Various unlisted makes/models
- Width: 57mm Baja SC50, Kymco, Panterra, QMB139 50cc/49cc , Roketa, SUNL, Schwinn, Tank, Various unlisted makes/models
Compatibility / Fitment
Use the fitment details below to confirm this part matches your scooter before ordering.
- Engine Size: 49cc, 50cc, QMB139
- Engine Code: QMB139
- Fits Models / Common Applications: Baja and other compatible models may apply.
- Fitment Notes: Universal Fit
Fitment Guide: This compatibility information is based on manufacturer and supplier data. Listed models are common known applications and may not include every compatible scooter. If your scooter has multiple versions or production changes, confirm the correct match before ordering. Check photos, measurements, original part numbers, engine code, model, and related fitment information whenever possible.
Common Fitment Questions
Q: Will this fit a QMB139 engine?
A: This SKU is listed as compatible with QMB139 engine-code fitment. Always compare your original part and scooter details before ordering.
Q: Will this fit a Baja?
A: This SKU is listed with Baja model fitment where the scooter also matches the listed engine or fitment notes.
Q: Is this for 49cc scooters?
A: This SKU is listed with 49cc engine-size fitment. Confirm exact model, year, and part style before ordering.
Additional information
| Weight | 0.3 lbs |
|---|---|
| Dimensions | 3 × 3 × 5 in |
Restore proper CVT engagement and shift behavior on your 50cc scooter with this Universal Parts replacement torque spring for 139QMB 4-stroke engines. The torque spring sits inside the rear driven pulley (clutch side) of the CVT and controls the rate at which the belt rides up the pulley faces as engine load increases. A worn or fatigued spring causes sluggish acceleration, belt slip, and poor top-speed engagement — replacing it restores factory CVT performance.
- 139QMB Fitment: Designed for the 50cc 4-stroke QMB139 engine platform used across a wide range of Chinese-made scooters
- 97mm Overall Length: Matches OEM torque spring length for compatible driven pulleys — verify against your existing spring before ordering
- 57mm Width: Outer coil diameter matches the driven pulley spring seat on compatible QMB139 CVT assemblies
- Conical Compression Design: Tapered coil profile provides progressive spring rate for smooth CVT engagement across the RPM range
- Steel Construction: Dark oxide-coated steel wire for corrosion resistance in the CVT housing environment
Fitment
Compatible with QMB139 50cc/49cc 4-stroke CVT scooters, including:
- Baja SC50
- Kymco (select 50cc models)
- Panterra
- Roketa
- Schwinn
- SUNL
- Tank
- Various unlisted Chinese 50cc QMB139-powered scooters
Technical Specifications
- Engine: QMB139 50cc / 49cc 4-stroke
- Overall Length: 97mm
- Width (outer diameter): 57mm
- Spring Type: Conical compression (torque / driven pulley spring)
- Material: Steel, dark oxide finish
- MPN / SKU: 151-144
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