Trying to track down a bleed kit for a non-Shimano brakeset in our office should have been my first clue. I mean, I’ve long been aware of the popularity of Shimano’s stoppers, but the blank stares and prevailing “sorry, I run Shimano” replies from my fellow dirt shredders drove the Japanese manufacturer’s dominance home. Fortunately, with good timing on my side, I’d heard a buzz about SRAM‘s new Guide brakes, which had just landed and were said to be quite the improvement over current models under the Chicago-based brand’s umbrella. I mounted up a set and have been running them hard for the past two months, experiencing the dependable braking power, control, and consistency to be spot-on, just as advertised. In short, any qualms with SRAM’s past braking systems were quelled with the new Guides.
The groundwork of the Guide was laid over a several-year testing period, in which addressing inconsistencies in its previous Avid XX and X0 models were top priorities. This clean starting slate allowed SRAM’s engineers to hyper-focus on refining engagement control, lever reach adjustment, and pad contact adjustment. A reworking of the guts was in order to meet these goals, and what resulted are three new Guide platforms, each with varying levels of customizable adjustability. The model that I’ve been testing is the top-end RSC (Reach adjust, Swinglink technology, and Contact-point adjust).
During installation, I noticed the boxy shape of the Guide brake lever’s master cylinder, which was quite the deviation from its prior assemblies. In addition to a reshaped bladder, this unit houses SRAM’s new Swinglink cam and Piggyback reservoir system. Replacing the long-employed TaperBore master cylinder of its Avid Elixirs, this new design relies on a sliding cup seal and port mechanism, which is the connection between the reservoir and master cylinder bore. It’s designed so that the moment the lever is squeezed, a cup seal swiftly passes this area and closes the port, pressurizing the system and forcing the pads to the rotor. This immediate actuation comes from the new cam-driven Swinglink, thus minimizing “deadband” at the lever (that time between engaging the lever and the pads contacting the rotor). Because of the reworked Swinglink cam position, SRAM says that the leverage rate smoothly transitions to a more linear curve once the pads contact the rotor, enabling you to “dance around the edge of lock-up.” In other words, you’re able to avoid that abrupt on/off feel, effectively giving you the balance of power and precise modulation.
The Guide relies on the same 4-piston, dual 14- and 16mm-diameter caliper used in the Trail brakes. Sintered metallic pads are standard, and the system runs on DOT 5.1 fluid. An updated “Centerline” rotor completes the package, relying on a series of elongated vents positioned directly in the braking track. The rotor incorporates a 12-spoke design, which is double that of what’s found on SRAM’s existing models. This new profile was designed to control the rotor’s warping and other lateral distortion that can occur when heated, in addition to aiding in overall cooling.
I mounted the short aluminum levers in a position that would provide solid single-finger operation, and after a few laps along the Shoreline above Salt Lake, I knew that the positioning was correct. The reach and contact point adjustments provide customizable options that serve to suit individual riders’ preferences, and I found that I needed only a slight adjustment to get the lever feel synched between the left and right side. The factory-bled system was dialed, and the feedback at the lever was immediate, without any of that “wait for the pads to grab” sketchy sensation. Pad-to-rotor contact was smooth, and the balanced feel and finessed control was a stark contrast to the current SRAM/Elixir-branded brakes. Just a light amount of pressure is all that’s required to produce maximum stopping power, which has meant less fatigue in my hands and arms, in addition to boosted confidence while getting into harrier situations.
Precise, silky lever feel aside, the Guides simply work. The calipers continue to do their job, as expected, but testing has yet to prove any notable difference in the new rotor design — as long as everything remains quiet and true, I’m not about to grumble. More long-term testing will tell if the system gets finicky, but in my two months of running them, everything’s been solid, without any of the sponginess, alignment issues, or other annoying quirks that seem to have plagued some SRAM stoppers over longer-term usage. This could be due, in part, to the clever new reservoir design, in which the flexible butyl membrane is placed directly above the cylinder and piston in order to further ensure protection from air and moisture entering the system.
The only real drawback I found was that the initial pad clearance kissed the rotors, regardless of caliper repositioning, but a few rides provided adequate break-in time that remedied this pretty quickly. And to be real thorough here, I’d also say that the contact-adjust knobs seemed to provide only minor differences in feel, unless maxed out at either end of the click wheel.
Overall, I’d say that the strongest characteristic of the Guides has proven to be the precise lever feel, combined with the exceptional power and modulation delivered through its new master cylinder. Being able to mount up a fuss-free setup was also a bonus, and the Guides have been nothing but dependable since day one. If you’ve been hesitant to jump on the SRAM brake train due to prior performance issues, testing has proven that they’ve been remedied with the Guides.
The brakes are available in three versions, with the top-shelf RSC model providing the most adjustability features, in addition to the Swinglink mechanism. The RS loses the Contact-point adjust, and organic pads replace the sintered metallic pads of the RSC. And finally, the value-oriented R version features Reach adjust and relies on SRAM’s standard Directlink instead of Swinglink. The RSC has a claimed weight of 375g for a complete front brake, and our in-house scales hit just below this mark at 369g.
– SRAM Guide RS & RSC Brakes * These will be hitting the shelves soon