Top End

The only safe way to maximize compression; the valve reliefs in the piston are purposely convex and match the geometry of the dishes in the valvesConversion to Black Diamond? stainless steel valves offers up to twice the life of the stock titanium...

The only safe way to maximize compression; the valve reliefs in the piston are purposely convex and match the geometry of the dishes in the valvesConversion to Black Diamond? stainless steel valves offers up to twice the life of the stock titanium...

Spring kit is designed with increased spring rates and high lift compatibility compared to the stock springsCompatible with boosted or turbocharged applicationsCNC-machined titanium retainers and Cr-Si dual springs provide valvetrain control at high rpms...

Replacement Spring Kit for Kibblewhite Top End Service Kit Yamaha -- YZ 250 F -- (2015, 2016, 2014); Yamaha -- WR 250 F -- (2016, 2015, 2014)

Keepers are made from high tensile strength steel Yamaha -- YXZ 1000R -- (2017, 2019, 2016, 2018)

All valve guides are made of Ampco-45, a high-performance compound with 80% copper content to provide great heat conductivity and 5% nickel content for wear resistanceMade in the U.S.A. Yamaha -- YXZ 1000R -- (2018, 2016, 2017, 2019)

Black Diamond? valves are CNC machined from one-piece forgings of EV8 Stainless SteelBlack Diamond? proprietary multi-stage process reduces friction, and provides superior resistance to corrosion and wearMade in the U.S.A. Yamaha -- YXZ 1000R -- (2017,...

Black Diamond? valves are CNC machined from one-piece forgings of EV8 Stainless SteelBlack Diamond? proprietary multi-stage process reduces friction, and provides superior resistance to corrosion and wearMade in the U.S.A. Yamaha -- YXZ 1000R -- (2017,...

Black Diamond? valves are CNC machined from one-piece forgings of EV8 Stainless SteelBlack Diamond? proprietary multi-stage process reduces friction, and provides superior resistance to corrosion and wearMade in the U.S.A. Yamaha -- YXZ 1000R -- (2018,...

Stainless steel conversion kits include only what's needed to convert your head to the long-life stainless steel Black Diamond? intake valvesExtend the life of the valvetrain and intake components by as much as 4x over the OEM titanium partsInclude...

Stainless steel conversion kit includes only what's needed to convert your head to the long-life stainless steel Black Diamond intake valvesExtends the life of the valvetrain and intake components by as much as 4x over the OEM titanium partsIncludes...

All valve guides are made of Ampco-45, a high-performance compound with 80% copper content to provide great heat conductivity and 5% nickel content for wear resistanceMade in the U.S.A. Yamaha -- YZ 250 F -- (2014, 2016, 2015, 2017, 2018); Yamaha -- YZ...