SRAM S-900 Aero HRD Disc Brake and Lever

SRAM S-900 Aero HRD Disc Brake and Lever Info

SRAM now offers hydraulic disc braking for triathlon bikes. The S-900 Aero HRD Disc Brake is small, light, powerful, and easy to use. If you’re thinking about getting a time trial bike with disc brakes, these stoppers make the decision easy.

The caliper is SRAM’s HRD, aka Hydraulic Road. This is the same as the eTap HRD, and is for road use only. It is a monoblock design, making the pushing of the steel-backed organic pads easy and consistent. The caliper mount is a flat-mount. When attaching to the fork, you use an adapter to get 0mm offset for 140mm rotors or 20mm offset for 160mm rotors. When attaching to the stays in the back, you use no adapter to get 0mm offset (140mm rotor), and 20mm offset (160mm rotor).

The brake lever is a sleek bar end plug design. The lever itself is molded carbon long fiber reinforced thermoplastic. The shape is small to the wind, but has plenty for your fingers to grab on to. Like SRAM’s HRD drop bar levers, there is reach adjustment, so you can nestle the lever so it easily fits where your fingers want to find it.

Installation is fairly simple. SRAM sets the calipers up with their DOT 5.1 fluid and hoses, so all you have to do is know how to install their Stealth-a-majig to the levers after threading the hoses through your frame. If you want to get the hydraulic hose length perfect, you’ll need a hose cutting tool, DOT grease, and then use their Bleeding Edge tool to do a quick bleed on the fluid to have everything tight.

The SRAM S-900 Aero HRD Disc Brake kit comes with levers, calipers, hoses, and fluid. Nearly everything is attached and ready to go. The left and right brake levers are identical. You’ll need to purchase rotors separately. SRAM recommends their 140 or 160mm rotors for the job.