Yamaha YZ 85 VFORCE4R Reed Valve System

The unique design of the VForce4R reed valve system for Yamaha YZ 85 features double the reed valve area of conventional reed valves. This has two advantages:

• The reeds only open half the distance of conventional reeds to achieve the same flow.
• By only opening halfway, there's a better chance of them being fully open and a better chance of sealing completely. By only opening halfway, they last longer as they don't experience as much pressure as conventional reeds opening as wide.

Improvements with VForce4:

• New resin, carbon fiber and lay-up reed system
• Pre-curved reed ensures better sealing at the tip
• Wider reed cage for maximum mixture flow
• Reed tip area increased by 10.5% resulting in increased total mixture flow
• Airfoil shape added to the tip of the cage to increase air speed to external ports
• Longer reed stops to progressively decrease the speed of the reed tip movement, for increased durability.
• Reduced central wing front area by 15.6% combined with a more aerodynamic shape.

New VForce4R features:

• Rubber over-mould on the reed tip surface to further improve petal life.
• Pre-curved reed ensures a better seal at the tip.

ATTENTION: This product is not a direct fit for the Yamaha DT LC 50. You will need to use, for example, an Athena 115cc cylinder or open the cylinder's intake.