39 mm outer diameter piston for 50cc GY6 139QMB engines. This is the stock size 39 mm piston for Chinese built 50cc GY6 139QMB engine. This piston in..
Standard (57mm) Barrel Kit, 157FMI, fits Engines of Chinese made SIZUKI EN125, GN125, GS125, etc. This kit comes complete with piston, rings, pin &am..