SSP-G QMB139 50mm Performance Cylinder and Head Kit. Includes cylinder, piston, piston rings, wrist pin, cir clips, complete cylinder head with 64mm valves, exhaust gasket, intake gasket, and cam chain tensioner gasket.

When used in conjunction with your stock crankshaft the displacement comes out to 82cc.

Please note: replaces Cylinder Heads with 64mm Valves (Short Valve Style). Please see Related Items if you need 64mm rocker arms.

• Upgrades to 82cc
• Cylinder Bore: 50mm
• Cylinder Sleeve Outer Diameter: 54.9mm 
• Intake Valve Diameter: 23.5mm
• Intake Port Diameter: 20.8mm
• Exhaust Valve Diameter: 20.1mm
• Exhaust Port Diameter: 18.8mm
• Valve Length: 62.3mm (compatible with 64mm Short Valve Style Heads) 
• Does not come with camshaft, please see Related Items
• Made in Taiwan