29mm stroke increases the displacement of your engine - that's 1mm more stroke than stock. It reduces crankcase volume, increasing compression. It must be used with 2 stacked cylinder base gaskets or cylinder kit when using Chung Yang engines. Same diameter as the stocks used on the G230RC.
Fits Zenoah G230RC / G260RC / G240RC / G270RC. Also fits Chung Yang / CY23RC / CY26RC / CY27RC engines