70cc Liquid Cooled Pentagonal Piaggio Big Bore Cylinder Kit. Kit includes cylinder, low-friction molybdenum coated piston, rings, piston pin, cir clips, head gasket and base gasket. When used in conjunction with a stock crankshaft the total displacement comes out to 70cc. Suitable for use with stock or performance exhaust. Fits models with the Liquid Cooled Piaggio engine including: Aprilia SR50 (2003-13) Derbi Atlantis (2002+) and GP1 (thru 2001) Piaggio NRG (1998+) and Zip 2 (1996-02) Gilera DNA and Runner *You may need to modify your engine case to accommodate the larger cylinder. Please see our Warranty Returns Policy.