Cylinder Kit NCY 171cc (61mm) for GY6 125cc & 150cc

NCY 61mm 171cc Cast Iron Cylinder Kit with Cast Aluminum Piston. Give your GY6-based scooter some serious power with this 171.3cc bolt-on kit for most 125/150cc GY6 engines. To our knowledge, this is the only 61mm cylinder kit for the GY6 engine that exists in the USA. With most 61mm cylinder kits, you have to cut the engine cases somehow to fit them (cylinder skirt OD: 65mm). This is not the case with the NCY 61mm 171cc Big Bore kit (cylinder skirt OD: 62.7mm). It also features a lightweight reduced piston to increase performance even more. It is highly recommended to squirt this kit significantly rich due to its high-performance capability. To maximize performance and efficiency, it is also recommended to get our large 61mm valve head . Some stock heads may not fit. 
 
Requires minimum bore clearance of 62.9mm or boring and machining is required.  

NCY 61mm 171cc Cast Iron Cylinder Kit with Cast Aluminum Piston. Give your GY6 based scooter some serious power with this 171.3cc bolt-on kit for most GY6 125/150cc engines. To our knowledge, this is the only 61mm cylinder kit for the GY6 engine that exists in the United States. With most 61mm cylinder kits, you have to cut the engine cases somehow to fit them (cylinder skirt outer diameter: 65mm). This is not the case with the NCY 61mm 171cc Big Bore kit (cylinder skirt outer diameter: 62.7mm). It also features a lightweight reduced piston to increase performance even further. It is highly recommended to squirt this significantly rich kit due to its high performance capacity. To maximize performance and efficiency, it is also recommended to obtain our large 61mm valve head. Some stock heads may not fit.

Requires a minimum bore clearance of 62.9mm or boring and machining is required.