HAYES Dominion A4

Hayes Dominion A4 Disc Brakes

With the 4-piston Dominion A4, Hayes has developed a new disc brake especially for trail, enduro, downhill and E-MTB applications.

High braking power with 4-Piston: Disc Brake Dominion A4 from Hayes

Dominion’s master cylinder is factory tuned for the shortest dead stroke possible and a crisp bite point. The Dominion A4 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.

With a motorsports-inspired Two-Stroke dual port bleed system, industry-leading DOT 5.1 fluid and Kevlar hose, the hydraulic system is engineered for ultimate performance across all temperatures and easy maintenance.

Features - Hayes Dominion A4

• 4-Piston Caliper
• Cartridge-bearings used in the brake lever
• Aluminum piston operates smoothly across operating temperatures
• Piston glide ring - technology pioneered in suspension forks
• Patented Crosshair caliper alignment screws
• Allows mechanics and end users to quickly and accurately set brake caliper with no rubbing of the rotor on the pads
• Eliminates guesswork and trial and error

Product features

• Use: MTB, E-Bike
• Model: Dominion A4
• Brake type: Disc-Brake
• Lever length: 2-Finger
• Open clamp: Yes
• Caliper: 4-Piston
• Brake mounting: Postmount
• Brake pads: T106 Semi-Melalic and T100 Sintered Metalic
• Brake hose length: front 1000mm / rear 1800mm (shortable)
• Brake fluid: DOT 5.1
• Recommended brake rotor: D-Series

Material

• Lever: Aluminum
• Caliper: Aluminum
• Piston: Aluminium for heat management

Weight

310g (manufacturer information)