Motorcycle 56.5 mm Piston 13 mm Pin Ring Set For CG125 ZJ125 CG ZJ 125 Engine Spare Parts This piston and ring set is designed for use with 56.5 mm cylinder bores and includes a 13 mm wrist pin. It is compatible with CG125, ZJ125, CG, ZJ, and 125 engine models. The set consists of a piston, connecting rod, wrist pin, circlips, and piston rings. Components are engineered for standard replacement and repair applications in motorcycle engines. This spare part supports engine rebuilding and performance restoration. Important: This product is an aftermarket alternative. Brand names mentioned serve only to show which devices it fits.