Universal Parts 681-17.7-30 Belt – 139QMB-B CVT Transmission

Reliable CVT Replacement: Universal Parts Standard CVT Drive Belt is designed for compatible 50cc scooters equipped with the 139QMB-B engine and B-case transmission.

Engine-Specific Fitment: The 681-17.7-30 belt profile is intended for transmission systems requiring these exact dimensions, supporting proper pulley engagement and consistent operation.

Durable Construction: Manufactured with a robust rubber compound and reinforced internal cords to help resist stretching and maintain reliable power transmission.

Optimized 30° Groove Angle: Designed for compatibility with matching variator and clutch pulley surfaces, promoting efficient power transfer and smooth transmission operation.

Heat and Wear Resistance: Built to maintain flexibility and grip under normal operating conditions, making it suitable for everyday scooter use.

Compatible Applications: Suitable for select 49cc/50cc 4-stroke scooters with 139QMB-B / QMB139-B engines, including compatible Roketa, TaoTao, and other B-series models.

Technical Specifications:

• Brand: Universal Parts

• Belt Size: 681-17.7-30

• Length: 681mm

• Top Width: 17.7mm

• Groove Angle: 30°

• Engine Compatibility: 139QMB-B / QMB139-B

• SKU: 106-92

• MPN: 3059

Maintenance Tip: Inspect the belt regularly for cracks, glazing, fraying, and excessive wear. Check the CVT air filter during belt replacement to help maintain proper airflow and reduce heat buildup.

Fitment Note: Verify your engine code and existing belt dimensions before ordering. This belt is intended for compatible B-case transmissions and may not fit applications requiring 669mm or 729mm belts.