72cc 47 mm High Performance Big Bore Cylinder Kit for 50cc QMB139 Scooter Engines

Our 72cc scooter big bore cylinder kit is great for increasing overall performance on small under-powered 50cc QMB139 scooter engines.

Engine kit increases engine bore size from 50cc to 72cc and includes everything shown in the image; cylinder, rings, and gaskets.

This 72cc scooter engine kit increases low end acceleration as well as top speed.

This high performance scooter big bore engine kit is easy to install. Combine with a high performance carburetor and high performance exhaust and get peak performance from your 50cc gas scooter.

Note: This high performance cylinder kit is only compatible with 4-stroke 50cc QMB139 engines.

⚠ WARNING California Residents: Proposition 65 Warning

Bore: 47 mm
Piston Height: 33 mm
Cylinder/Cylinder Head hole spacing: 50 mm x 50 mm
Piston Wrist Pin Diameter : 12 mm
Piston Wrist Pin Length: 37 mm
Compression height : 17 mm
Ring Diameter: 47 mm