By Justin Steiner
SRAM has long touted the breadth and diversity of their XO group, given it’s ability to span the performance spectrum from XC race to DH race. For 2013, Avid will further broaden their offerings with two unique models of the XO brake to better meet the needs of riders across these diverse disciplines. The XO Trail brake will cater to those on the trail/all mountain/gravity end of the spectrum, while the lighter XO brake shaves grams for the weight-saving crowd.
The new four-piston XO Trail brake bridges the gap between Avid’s gravity-centric Code models and the existing two-piston XO brake. Avid added sealed bearings at the lever pivot for a silky-smooth lever feel in addition to their tool-free reach and pad contact adjustments.
The new two-piston caliper features different sized pistons, 16mm front and 14mm rear, which offset the center of pressure to minimize squealing and maximize smoothness. Unlike the current XO model, the XO Trail brakes come stock with an aluminum-backed organic pad, while sintered pads will be an optional upgrade. Said new pads are specific to the XO trail brake.
Interestingly, Avid is moving away from their Caliper Positioning System (CPS) washers with both of these new brakes. As manufacturing has improved over the years, Avid has found frame and fork mounts to be accurate enough to eliminate the CPS washers on some models.
With the addition of two pistons and sealed bearing pivots, weight went up just 7 grams from last year’s XO brake—from 333-grams to 340-grams.
The Taperbore master cylinder of both models has been updated with all of the changes we saw on last year’s Elixir 9 & 7 models including new reservoir bladder material, better sealing, and Air-Trap to keep any errant bubbles out of the high pressure portion of the system. These changes intend to mitigate air contamination of the system. I’m currently testing a pair of Elixir 9 brakes and have found them to be trouble-free to this point, so these changes appear to be an improvement.
All of these changes were driven by the desire to create the ultimate mountain biker’s brake. Something with better lever feel, more power, and more control than existing brakes. After riding the XO Trail brakes a few weeks back at the SRAM press launch, I feel Avid has met their goals admirably. Level feel is wonderfully smooth thanks to the bearings, and the lever setup is as easy as every. Power and modulation were both stellar with the organic pads, offering fade free performance on some demanding terrain.
I can’t wait to get my hands on a set of these brakes for long-term testing. XO Trail brakes will be available in Black Ano and Silver Polished finishes sometime in July for $310/wheel.
The 2013 XO brake prioritizes weight savings now that the Trail brake is able to take the bulk of the gravity performance burden. In order to trim weight down to 315-grams, Avid ditched the pad contact adjustment and the CPS washers. Fortunately, these brakes retain tool-free reach adjustment.
We didn’t have a chance to sample the XO brake, but performance should be in line with the existing XO brake. The XO model will be available in Red, Silver, and Black sometime in July for $261/wheel.
New Rotor Size
Avid also announced a new 170mm rotor diameter in the HS1 rotor family. According the SRAM, they want to give riders options for their various wheels sizes and terrain needs.