Making power is easy. Making power with the right feel, therefore Hayes created an all new system. The result is the Dominion A4 which is suitable for Trail, Enduro, Downhill and E-MTB use as well.
Highlights of the Hayes Dominion A4 disc brake
- all new development with four-piston technology
- ball bearing mounted lever for better braking sensation
- tool-free dead stroke adjustment
- aluminium pistons for heat management
- very stiff brake caliper
- 2-Stroke Dual Port Bleed System for safe venting
- brake pad bolt pin simultaneously serves as third screw for caliper stiffening
- Crosshair caliper alignment system
Ball-bearing brake lever with tool-free dead stroke adjustment
With the brake lever, the focus is on achieving as high a braking force as possible with as little finger force as needed. This is to prevent unnecessary waste of force during hard braking. To achieve a crisp bite point, the master cylinder is factory tuned for the shortest dead stroke possible. Meanwhile the lever of the Dominion features a robust design and allows a lever width adjustment without tools.
New developed 4-piston brake caliper
The brake caliper of the Dominion A4 is a completely new development and promises extreme brake power. There is an adjustment for the lever travel and the associated position of the encoder piston. The disc brake promises intuitive braking behaviour and has a defined increase in braking force when pad the pads hit the disc. This ensures a high degree of predictability and control. The caliper utilizes four pistons in the most structurally rigid design possible. It features a cold-forged caliper and KingPin structural pad retention bolt that increases stiffness. Hayes is especially proud of the venting system: the 4-piston caliper is equipped with two vent openings to ensure optimum venting. The position of the brake caliper can be adjusted to the brake screw connection using a 2 mm grub screw.
