S3 Star cylinder head kit for Gas Gas Enduro motorcycles 2017 and older. We use the best alloys available, to obtain a better output & more traction. Star Head's can hold more water and have thicker walls helping with the cooling rate, thus improving low revs power. These kits eliminate the hot spots typically found on cast heads. Specific compression inlet design offers the possibility to adapt engine setting to YOUR desired compression. Kit includes standard, high, and high high compression inserts.