Kibblewhite 80-80080 Guide Intake Std Yamaha Wr/yz250f 01-11

Valve Guides, Seals and Tappets

KPMI Bronze Valve Guides:

We choose to use C630 nickel bronze as a material to make valve guides because of its ideal characteristics for the application. The 4-5 percent nickel content provides superior resistance to wear, and the approximately 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. The top portion of the guides are shortened when cam lift information available at the time of design shows that additional retainer to seal clearance is required.

KPMI Tappets:

KPMI engineers design our tappets using advanced finite element stress analysis software. This software allows our engineers to lighten the tappets without sacrificing strength, so we can create the strongest, lightest tappets possible.  These tappets are machined from aircraft quality solid steel bar stock. They undergo a proprietary heat treatment process that creates a hard surface and a non-brittle core, maximizing toughness and wear resistance. KPMI tappets are run in high performance automotive and motorcycle racing applications including Motocross, Flat Track Racing, Road Racing, Drag Racing, and Land Speed Racing at the Bonneville Salt Flats.

FOOTNOTE: § = Use OEM Valve Stem Seals