Introducing the worlds first Billet CNC Machined Valve Covers available to the public!



First on deck in limited quantities – finally after months of development – the RMZ450 Billet Valve Cover. 

  • Billet 6061 aluminum which is stronger than OEM magnesium. 
    • Stiffer material – means we can add to the gasket compression to solve that oil weeping.
    • In addition to the stiffer material, the structure was beefed up with ribs extending from the mounting holes to better distribute the bolt loading when compressing the gasket.
    • Nothing wrong with magnesium!  Great OEM material choice for inexpensive mass production.  Light and easy to cast.  But in this application – we spent extensive time optimizing the geometry to provide a stiffer structure within a few grams of being equal in mass to the OEM cover.  A valve cover can benefit from greater stiffness because it needs to load and compress the rubber gasket.
    • Heat transfer is greater with aluminum.  Not a significant factor on the top of the head but science is science!
  • Next up are the YZ250f and RMZ250.  Eventually we will get to all of them!  Please feel free to pester us and help us keep the priorities in the right order.