DDM 29CC CY 35MM BIG-BORE CONVERSION KIT INCLUDES +2MM STUFFED STROKER CRANKSHAFT35mm bore cylinder plus 2mm stroker crank gives an effective displacement of 28.9cc! Kit includes: 35mm cylinder, 35mm piston, piston ring, piston pin, pin washer set, pin bearing, circlips, cylinder gasket, CMR7H spark plug, and STUFFED 2mm stroker crankshaft (30mm stroke, up from 28mm stock stroke). The squish on the cylinder has been pre-machined to accept the 2mm stroker using only the standard .020" cylinder gasket. Provides HUGE increases in engine power, allowing you to use taller gearing for more top speed! This high-performance product requires 91 octane (using the R+M/2 octane rating method) or higher fuel, and comes without warranty. Fits G23LH / G230RC / G260RC / CY23RC / CY26RC / CY27RC / CY29RC engines.