Cylinder & Head Big Bore Kit - 61mm GY6 125cc/150cc Scooter, ATV & Go-Kart

Alloy cylinder and head big bore kit for GY6 125cc/150cc 4-stroke scooters, ATVs and go-karts. This performance kit may require modification to the engine case bore.

Compatible with Honda-based GY6 engines and Chinese-cloned GY6 152QMI and 157QMJ engines. Does not fit P152QMI or P157QMJ engines.

Kit Includes

• 63mm Aluminum Cylinder Head
• 63mm Aluminum Cylinder Block
• High Performance Camshaft
• Piston and Piston Rings
• Wrist Pin
• Wrist Pin Clips
• Gaskets

Specifications

• Cylinder Diameter: 61mm
• Outer Sleeve Diameter: 64.95mm
• Bolt Hole Spacing: 54mm center-to-center
• Intake Valve Diameter: 28mm
• Exhaust Valve Diameter: 23mm
• Exhaust Port: 27mm

Compatible With

• Honda-based GY6 125cc/150cc engines
• Chinese-cloned GY6 152QMI and 157QMJ engines
• KYMCO GY6 125cc/150cc
• MXer GY6 125cc/150cc
• MXU GY6 125cc/150cc
• TGB GY6 125cc/150cc
• HONDA GY6 125cc/150cc
• SYM GY6 125cc/150cc
• VENTO GY6 125cc/150cc
• Phantom R4i GY6 125cc/150cc
• Strada RX150
• Yamati GY6 125cc/150cc
• Verucci GY6 125cc/150cc
• Baccio GY6 125cc/150cc
• Viva GY6 125cc/150cc
• Matrix GY6 125cc/150cc
• Wuzzi GY6 125cc/150cc
• Lifan GY6 125cc/150cc
• GY6 125cc/150cc clones

Important Fitment & Installation Information

• Does not fit P152QMI or P157QMJ engines.
• This kit is not recommended for inexperienced installers.
• Installation by an experienced scooter or motorcycle mechanic is highly recommended.
• Valves may require adjustment and engine timing must be properly set.
• In most cases, the engine case must be bored to accommodate the larger 64.95mm cylinder sleeve.