Universal Parts QMB139 50mm Big Bore Cylinder Kit
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This Universal Parts 50mm Big Bore Cylinder Kit fits 50cc 4-stroke 139QMB engines, upgrading bikes to 81.3cc based on a stock stroke of 41.4mm!
Specifications:
- Includes cylinder, piston, pin, circlips, rings, head gasket and base gasket
- Bore: 50mm
- Overall Height: 70.5mm
- Cylinder Sleeve Outer Diameter: 53mm
139QMB-based 50cc / 80cc engines with the following engine codes:
| 139QMA | 139QMB | 1P39QMB | 1P39QMA-2 |
| YN139QMB | JJ1P39QMB | 139FMA-2 | BD1P39QMB |
| BN139QMB | 147QMD | Other QMA models | Other QMB models |
Don't see your engine listed? If the engine code includes "QM" or "FM", this product is compatible with your vehicle.
NOTE: You may need to modify your engine case to accommodate the larger cylinder.
About Scooterworks: Since our beginning in 1989, Scooterworks has become a major supplier of parts and accessories for vintage and modern scooters. We have everything you need, from wear-and-tear items like tires and oil filters to after-market parts from brands like Malossi, NCY, Prima, YSS, Dr. Pulley, and more.
This product is not intended for use on public roads or land.
Shipping information
Orders are prepared as quickly as possible. Delivery times and shipping costs are calculated at checkout based on the destination and items ordered.
Returns & warranty
Please verify fitment and part number before ordering. Contact Thrifty Scooters promptly if an item arrives damaged or incorrect.