SRAM Announces New Aero TT Hydraulic Brake System

Today, SRAM made a big leap forward in the triathlon/TT world by announcing its new S-900 Aero HRD Hydraulic Disc Brake system—a first among major component manufacturers. The new hydraulic SRAM levers are brake-only (not integrated with eTap shifting yet) and boast “optimized power and modulation for triathlon and time trial,” according to SRAM’s release. SRAM says that the new HydroT system is aero-specific and will offer excellent feel and control. The levers themselves are a textured carbon that will likely be useful to wet triathletes with slippery digits.

The details so far:

Available in September, the S-900 Aero HRD disc lever/caliper combo will run about $249; the rotor will have an MSRP of $72. The Calipers themselves are flat mount only, and SRAM recommends either a 160mm or 140mm Centerline X rotor for TT/tri. Claimed weight is 240g. Fearful home mechanics who have heard brake-bleed horror stories should rest easy as SRAM is incorporating their Bleeding Edge technology that they claim takes “ninety seconds from dry to a solid bleed.” The S-900 is also equipped with reach adjust for different-sizes hands and fingers, while their patented Stealth-A-Majig connector boasts quick and easy initial setup.

Why this matters:

While the last year has seen a rise in disc brake setups on road bikes, tt/tri bike brands have been slightly slower to adapt: Triathletes have had bikes (the Parlee TTiR, Diamondback’s Andean and Cervelo’s P5x) that are disc-equipped, but unless you’re ready to do some serious hacking, these models are mostly mechanical-disc bound.

Simply put, road bikes are moving in the direction of disc brakes—just like mountain biking did a very long time ago. (For more about disc brakes, see our story from April.) And just like in mountain biking, high-end tri bikes will go the hydraulic disc route, while mechanical disc-options will likely remain for budget-conscious athletes. With this announcement, SRAM has stepped up to become the leader among the major component brands.

What’s next:

Shimano has had a page on their website that lists the features of the mysterious ST-R9180—an aero lever that is not only hydraulic, but also has shifting capabilities. TRP also announced the TT Hydro back in March, but those still aren’t available either. Now that bike brands can ensure that their superbikes will have super-hydraulic disc brakes—instead of mechanical half-measures—it’s likely that more disc-equipped bike models will follow. To prove the point, just a few days ago we saw spy shots of Cannondale’s new Super Slice Disc at Le Tour.

Specifications for SRAM S-900 Aero HRD Disc Brake:

WEIGHT 240g
LEVER MATERIAL Carbon LFRT (long fiber reinforced thermoplastic)
CALIPER DESIGN Monoblock
FINISH Black Anodized
ROTOR 2-piece CLX 140 or 160
PAD Steel-backed organic
FLUID DOT 5.1
MOUNT Flat mount 0 or 20mm offset
ADJUSTMENT Tooled reach adjust
MATERIAL Forged aluminum, carbon LFRT
PIVOT Bushing
ROTOR SIZES 140mm, 160mm
TOOL-FREE PAD REPLACEMENT Yes
AMBIDEXTROUS Yes
STAINLESS HARDWARE Ti and stainless