To SRAM, the original Guide was much more than a new brake. Truthfully, it was a redeeming Hail Mary, thrown in hopes of regaining consumers’ trust after the era of the Avid Elixir.
We’ll have our long term review up soon, but the short version is this – the Guide brakes really are the brake SRAM needed. Big on power, good ergonomics, and smooth at the lever, the Guides were a perfect match with the new CenterLine rotors. In spite of how good the Guide brakes turned out, they’re about to get even better with the new Guide Ultimate. More than just a carbon lever and some titanium parts, the Guide Ultimates include an all new caliper, new bleed technology, and a lighter CenterLine X rotor to go along with it…
Part of the allure of the Guide has always been the power of a 4 piston brake caliper but the weight of a trail brake, making it the perfect brake for anything from aggressive trail to full on Enduro. While keeping the 4 piston portion of the design, the rest of the caliper gets an overhaul in almost every way. Called the S4, the caliper body has revised gland geometry, seals, and a Molybdenum piston coating for better roll back (when you let go of the lever and the pads retract). This should make for more pad clearance allowing easier set up and more consistent performance without slowly cinching down on the rotor and causing rubbing.
Heat management has been improved as well with a new 2mm larger pad pocket for better airflow around the pads and the rotor. Phenolic piston insulators sit inside the forged 14 and 16mm aluminum pistons which reduce the heat transfer from the pad to the piston, but keep an aluminum surface at the piston seal for improved durability. The new molded seal offers better cold weather performance and should be more consistent than previous seals. Additional heat regulation is provided through patent pending aluminum heat shields that sit between the pad and the caliper body which claim to reduce fluid temperature by almost 20ºc.
The last big change to the caliper comes in what SRAM is calling Bleeding Edge Technology. Thanks to revised bleed porting and fluid path, the new calipers should be easier than ever to chase out any bubbles. Better bleeding does come with one catch – the new calipers will require their own specific bleed adapter. According to SRAM the adapter plugs into the bleed port and seals the system which prevents air from entering the system or fluid loss. Adapters will be included with each brake to make sure the requirement won’t keep your bike in the shop instead of out on the trail.
At the bar, other than the new carbon brake lever and titanium hardware, the Guide Ultimates retain much of the same technology found on other models including Swinglink lever geometry, a flip flop design, and tool free contact point and reach adjustment. Using aluminum calipers and levers, claimed weight is listed at 360g for a complete front brake including rotors, adapter, and bolts. Compatible with current SRAM Guide brake pads, Guide Ultimates will be available in May, and in Arctic Grey Ano or Black Ano.
Slotting in above the current CenterLine rotors, the new CenterLine X rotors are a perfect complement to the Guide Ultimates. Using the same cut out pattern that has proven to be quiet and consistent, the CenterLine X rotors add an aluminum center carrier to reduce the weight. Available in July, the CenterLine X will be sold in 140, 160, and 180mm sizes in both 6 bolt and Centerlock. Claimed weights are listed at 86g (140mm), 102g (160mm), and 125g (180mm).