Hayes Dominion A4

The Dominion A4 is purpose-built for aggressive mountain biking, specifically downhill and enduro riding. Its four-piston design is engineered to handle the high speeds, steep descents, and technical terrain where consistent, heavy-duty stopping power is essential.

The Hayes Dominion A4 utilizes DOT 5.1 fluid. This is important to note for maintenance, as you should only use compatible fluids and bleed kits designed for DOT systems.

The woven Kevlar hose is designed to be exceptionally stiff, which minimizes hose expansion under high pressure. This ensures that the force you apply at the lever is transferred directly to the caliper, resulting in a more responsive and consistent feel at the wheel.

The Dominion A4 uses a standard 74mm post mount, which is the industry standard for most modern mountain bike forks and frames. As long as your bike uses this mounting interface, they should be compatible.

The QuickBite2 compound is specifically formulated to provide reliable performance across a wide range of temperatures and speeds. It is designed to offer a balance of immediate bite and long-term durability, which is crucial for maintaining control on long, technical descents.