Custom 34mm big-bore head kit from legendary 2-stroke engine tuner Trevor Simpson. Displacement of 25.4cc when used with stock 28mm crankshaft. Kit includes:

Machined 34mm cylinder, billet head with engraved signature and cooling fins, 13:1 compression dome, piston, piston ring, piston pin, circlips, cylinder gasket, NGK CMR7H spark plug, mounting hardware, and instructions. Increases the power and speed of your engine SUBSTANTIALLY! Fits Zenoah G23LH / G230RC / G260RC engines. Also fits Chung Yang CY23RC / CY26RC engines. Requires 91 octane (using the R+M/2 octane rating method) or higher fuel. Note: if installing this product onto a Chung Yang engine (CY23RC, CY26RC, etc), you will need to use a Zenoah pin bearing and Zenoah pin washers.