Airsal 77cc Racing cylinder kit, complete with all necessary parts, such as gasket set, piston, piston rings, etc. incl. cylinder head. The 77cc Tech-Piston has the same timing as the 77cc Racing and has a 2-Piece outlet. The difference is the high quality MAHLE piston (1 ring). Aluminium with hard-chromed bore. No need to work the crank cases on this model.