47mm GY6 50cc (139QMB) Cylinder Kit

47mm Cylinder Kit for 139QMB 50cc Engines

This performance cylinder kit is designed to upgrade your 50cc QMB139 engine to a powerful 72cc. It includes all necessary components for installation, making it a practical choice for those looking to improve their scooter's performance. This product is one of the GY6 50cc scooter parts that can significantly boost acceleration and overall engine response. Keep in mind that modifications to the engine case may be necessary to accommodate the larger cylinder.

Components Included

The kit comes complete with a cylinder, piston, piston rings, piston pin, circlips, a head gasket, and a base gasket. These components work together to ensure reliable performance once installed. Each piece is designed to fit well within the engine, providing a straightforward upgrade path for scooter enthusiasts.

Performance and Specifications

The cylinder features a bore size of 47mm, with a sleeve outer diameter of 52.7mm. The wrist pin diameter measures 13mm, and the total piston height is 34.4mm. Additionally, the compression height from the center of the wrist pin hole to the top edge of the piston is 17.25mm. These specifications ensure that the upgrade yields the desired increase in displacement and performance.

Specifications

• Cylinder Bore: 47mm
• Wrist Pin Diameter: 13mm
• Total Piston Height: 34.4mm
• Compression Height: 17.25mm
• Included Components: Cylinder, piston, rings, piston pin, circlips, head gasket, base gasket

Fitment

This cylinder kit is compatible with 139QMB-based 50cc and 80cc engines. The following engine codes are applicable:

• 139QMA
• 1P39QMB
• 1P39QMA-2
• YN139QMB
• JJ1P39QMB
• 139FMA-2
• BD1P39QMB
• BN139QMB
• 147QMD

Not sure it fits? Contact us with your scooter's make, model and year and we'll confirm the fit before you order.

Shop more: GY6 50cc Scooter Parts (139QMB) · GY6 Scooter Parts · Scooter Big Bore & Cylinder Kits · Scooter Parts