The Disc Brake has seen countless advancements and improvements over its century-old lifespan. However, in recent years, it's been adapted to the mountain bike, and this iteration commonly relies upon motorsports for guidance on everything from technology to materials. And while this trickle-down relationship has brought benefits, a new name in the American mountain bike market, Brake Force One (BFO), is breaking up with motorsports in order to forge a fresh, mountain-specific design to the old disc brake.
Hydraulic disc brakes require a reservoir to allow for fluid expansion. Cars have them, motorcycles have them, and well, any device that uses hydraulic disc brakes has a reservoir. That is, any device except BFO's disc brake. Instead, its design uses larger-bored hoses and a radial master cylinder, along with a hydraulic booster, in order to eliminate the need for a reservoir.
The hydraulic booster, located inside of the alloy caliper, is a two stage system that, when initially activated by lever movement, quickly engages the pads to the rotor with little effort. This compensates for the wider, noise-reducing and heat-dissipating clearance between the pads and rotors of these brakes. Once in contact with the rotor, resistance switches a valve that activates a secondary, larger piston. The result is more fluid volume being moved for tons of power in a lower pressure system. Ultimately, this requires less effort on your part. In fact, so little effort is needed that BFO's brakes are designed for dedicated one-finger braking.
The levers are constructed from a lightweight carbon resin, as is the master cylinder body, and it features a rubber pad for comfort. But, more importantly, this system creates a secure connection between your gloves and the lever. The master cylinder's piston and bore is 2.5 times larger than any other currently available, and between it and the innovative caliper is a new hose design unlike anything else. The hose is transparent, and it has one of the largest internal bores available today. This, like the oversized master cylinder, allows more fluid volume for cooling capacity, and it ensures that input from the lever is instantly transferred. The transparent lines are advantageous because they ease bleeding and maintenance, as you can see air bubbles and oil degradation without opening up the system.
Brake Force One uses mineral oil, and it offers seven color options -- visible through the clear hoses -- to personalize your brakes. The brake will ship with clear fluid, but you can purchase the colored fluid and the bleed kit separately. The caliper is constructed from aluminum and it's designed for post mounts. Brake Force One has a complete line of CNC-machined adapters, and they recommend a 180/160mm rotor combination for XC, and a 203/180mm setup for DH.
If you're reluctant to try a new system, keep in mind that this is the second generation of BFO's disc brake. It's already been proven in the European market, and basically, BFO is only a fresh face on this side of the pond.
The Brake Force One Disc Brake is manufactured in Germany to high standards and is sold individually as a front or a rear in the colors Black, Matte White, and Red.