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Universal Parts QMB139 50mm Big Bore Cylinder Kit

Original price $70.00 - Original price $70.00
Original price
$70.00
$70.00 - $70.00
Current price $70.00

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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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