KPMI takes a scientific “System” approach when designing our Valve spring kits. Each component is designed to work with the others as part of the complete system. KPMI’s engineers use our proprietary design and simulation softwares, and draw on our 70+ years of design experience to create these systems. Our design, simulation, and manufacturing processes insure compatibility of the valve spring’s force and natural frequency with the cam profile, valvetrain mass, system harmonics, and the engine RPM. Our spring manufacturing partners are U.S based companies that are ISO certified. The Super-Clean Chrome Silicon valve spring wire we use is traceable back to Kobe Japan where some of the best spring wire in the world is manufactured. Combining our design and simulation protocols with this premium quality valve spring wire, and manufacturing processes including, heat treatment, stress relief, and shot peening, allow us to supply you with the best valve springs in the world.
Model TRX™ 400EX
Year 1999 to 2007
Type Racing Valve Spring Kits
Description 0.460" valve lift OK
Retainers 30-3112, Titanium Retainers Honda® TRX™ 400EX 1999-2008
Keepers Use O.E.M.
Springs 30-3113, Chrome Silicon Springs Honda® TRX™ 400EX 1999-2008