Valve Black Diamond™ Kibblewhite (Manufacturer part number: 30-31466) — machined exhaust valve for motocross engines. Made from forged monoblock EV8 stainless steel and CNC machined, this valve is aimed at demanding riders looking for a durable, precise part optimised for the exhaust flow of high-performance cylinder heads.
- Type: Exhaust valve
- Material: Forged monoblock EV8 stainless steel
- Treatment: German process at 0.002" depth, surface layer 0.0002" — better wear resistance and reduced friction compared to chrome or electrolytic nickel plating
- Machining: CNC; profiles validated by F.E.A. and computerised flow bench
- Stem: Black Nitroneg coating
- Tulip angle: 20°
- Head diameter: 0.984" / 25.00 mm
- Manufacturing: United States
Ideal for motocross engines, this Black Diamond™ valve features flow-tested profiles to optimise gas flow and reduce losses due to friction. Its machining and surface treatments provide strength and longevity in the demanding conditions of off-road use. Compatible notably with Honda CRF 250 R (ME10) — models from 2013 to 2015. Replaces the original valve for precise guidance and enhanced performance under heavy load.