High performance head for 4 stroke

This high quality, high performance head assembly matches the 80cc big bore kit we sell. Unlike 2-strokes, the power of a 4 stroke depends mainly on the head design. This head has been completely redesigned to achieve lots more power from your scooter's engine, by introducing stiffer double valve springs, bigger intake/exhaust valves, increased port size for maximum flow and a good squish area to create turbulence in the combustion chamber, resulting in increase swirl and efficient combustion. Works best with the 80cc big bore kit. To suit: Chinese air cooled 4 stroke engines with QMB139 type engines (fits nearly all 4 stroke 50cc Chinese, may include Huawin, Motostar, Baotian, Boatian, Solana, Arrow, Fierce, Forza, "Factory Built", Wolfboy, Qingqi, Kinroad etc also other generic brands registered as "Moped" etc)