Up for sale is KPMI 2000-2004 YFM400 Big Bear 2WD [SRA] Yamaha INTAKE/EXHAUST VALVE GUIDE (BRONZE). The vendor part number is 80-8010. Please read the title to know what is for sale We choose to use C630 nickel bronze as a material to make valve guides because of its ideal characteristics for the application. The 5 percent nickel content provides superior resistance to wear, and the 80 percent copper content delivers outstanding heat conductivity. Guide profiles are designed to have minimal effect on the airstream while maintaining critical cross sectional thickness in high temperature areas, promoting high performance and endurance.