
Valve Black Diamond™ by Kibblewhite — premium intake valve designed for enduro and motocross. CNC machined from a monobloc forging in EV8 stainless steel, it combines strength and optimised geometry for controlled flow in the manifold. Each piece is validated by finite element analysis (F.E.A.) and tested on a computerised flow bench to ensure consistency of profiles.
The monobloc design and studied profile are suitable for the demanding cylinder heads of motocross and enduro machines, while facilitating consistent operation and longevity. Note: installation requires the use of the appropriate Kibblewhite spring kit — ensure the correct distribution hardware is available when refurbishing the cylinder head.
Manufacturer reference: 80-80075. Compatible with many 250 cc models (e.g. Yamaha YZ/WR 250 F depending on configurations), please consult your motorcycle specification for confirmation of fitment before installation.