BCV Cup Kits improve hand feel to the rider
BCV Cup Kit: this kit addresses the sudden fast movement of the forks. Examples can be a square edge bump at speed, a log on the trail or hammering a whoop section. Better high speed compression movement of the fork means the impact is now absorbed and not transmitting to the riders arms and shoulders.
The BCV Cup Kits unique design is essentially a check valve that meters oil flow, when the fork encounters a sudden hard hit the valve opens allowing the forks to compress quickly soaking up the impact.