Fit For 180cc Cylinder 61mm Bore For GY6 125cc 150cc 1P52QMI 1P57QMJ Motorcycle Engine Parts Fit For GY6 125cc 150cc 1P52QMI 1P57QMJ Scooter Fit For 61mm oversized bore upgrades displacement to 180cc for stronger low-end torque faster acceleration cylinder liner delivers outstanding wear resistance for long-distance daily commuting machined cooling fins improve dissipation to avoid overheating under heavy load riding Standard mounting port layout consistent with engine case for bolt-on installation without frame Matched dimensional tolerance ensures seamless fit with corresponding piston, rings head components