88cc Big Bore kit and 20mm Carburetor kit Kit: - Lightweight aluminum cylinder with steel sleeve - Cast in mounts on cylinder for aftermarket skid plates - Oversized cooling fins on cylinder for efficient heat dissipation - High compression 52mm piston with rings, pin, & clips,Head gasket kit - 20mm Performance carb assembly. Includes: 20mm carb, intake, heatstop, gaskets, mounting hardware/wrench, air filter and long throttle cable. A main jet kit is now included too! Easily double your power and fun with this quality, yet economical bore kit!! We recommend purchasing a HD Clutch also to keep up with the added HP.