NCY 81cc Aluminum Performance Cylinder Head. Great quality alloy cylinder head designed to work seamlessly with 1100-1237 81cc cylinder kit. Give your 139QMB the power to handle today’s city traffic. You can use this cylinder on all 139QMB engines from SYM, Kymco, QLink, Filly 50 as well as other Chinese scooters with the 139QMB engine. Note:Rocker arm assembly (part # 1100-1326) may be required for some models. Please check the valve stem height as it relates to the rocker arms installation. Be sure to add an exhaust, upgrade your carburetor and air filter for a complete upgrade.