NCY 171cc Big Bore Kit (61mm) - No Case-Cut for GY6

NCY 171cc Big Bore Kit (61mm) – No Case-Cut for GY6 150 The NCY 61mm Cylinder Kit is the only 171cc upgrade available in the U.S., designed to fit without machining your engine cases. Featuring a specialized 62.9mm outer skirt, this aluminum cylinder drops directly into standard GY6 150cc blocks. It is the ultimate "weekend project" for riders demanding a massive jump in torque and acceleration without the need for professional machine shop services. The NCY Performance Advantage True Bolt-On Engineering: Slim-skirt design eliminates the need to "split the cases" or grind the engine block for clearance. Advanced Thermal Cooling: All-aluminum construction dissipates heat significantly faster than stock cast-iron cylinders, preventing power fade during long-distance riding. High-RPM Piston: Includes a specialized "short-skirt" racing piston to reduce reciprocating mass, allowing for faster revving and higher top-end potential. Comprehensive Kit: Includes cylinder, piston, rings, wrist pin, clips, and performance gaskets. Detailed Model Fitment Category Compatible Models / Codes Genuine Scooter Co. Buddy 125, Buddy 150, Buddy 170i, Hooligan 170i, Blur 150 Go-Karts / Buggies Hammerhead 150, Trailmaster 150 (all variants), Yerf-Dog, Carter Talon Chinese GY6 Brands TaoTao, Wolf, Ice Bear, Bintelli, Peace Sports, ZNEN, SSR, Kymco Engine Codes 157QMJ, 1P57QMJ, 152QMI, 161QMK, BN157QMJ, BN161QMK-A Technical Specifications Displacement: 171.3cc (61mm Bore) Outer Skirt Diameter: 62.99mm (Direct Fit) Material: High-Grade Aluminum SKU: 1100-1288 IMPORTANT FUELING NOTE: A big-bore kit requires significantly more fuel. You must upjet your carburetor (typically to a #125 or #130 main jet) to prevent a lean condition. To reach the full power potential of 171cc, we highly recommend pairing this with the NCY Big Valve Head (SKU 1100-1254) . This product is not intended for use on public roads or land. This product is not legal for use in California on pollution-controlled vehicles. Check local laws before installation. California Prop 65 Warning: www.P65Warnings.ca.gov