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.
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