NEW SRAM Guide Ultimate Disc Brakes Stands Alone as the Leader in its Class

SRAM's Most Advanced Braking System EVER

Product Photos: Ryan Palmer

bikemag.com

Completely new, the SRAM Guide Ultimate has a 4-piston S4 caliper, SwingLink lever cam, and a carbon lever blade. The 360-gram brakeset has been engineered to be light and powerful, with superior heat management capabilities, which give you better, more consistent, more reliable braking. The new caliper design also incorporates a re-designed seal and aluminum piston interface for ease of setup and improved consistency, while Bleeding Edge technology makes bleeding Guide Ultimate a quick and easy task.

The Guide Ultimate master has all the same guts as the Guide RSC, but is dressed with a carbon lever blade and titanium hardware.

There’s a whole lot more to these new stoppers than carbon levers and fancy bolts. The real magic of the SRAM Guide Ultimate is in the all-new S4 caliper. Aside from needing to maintaining piston size and pad shape, engineers were given free reign to design the ‘ultimate’ caliper to mate with the already-impressive Guide master. SRAM’s main goal with the S4 caliper was to create a brake that feels exactly the same every time you pull the lever. This is accomplished by managing heat, creating super-consistent seal/piston rollback, and simplifying the bleed.

This little piece is a heat shield, and it’s responsible for significantly lowering the running temperature of the Guide Ultimate. SRAM experimented with heat shields around the whole pad opening, but found that the most significant gains were made in just the one location.

The black caliper on the left is the existing Guide caliper, and the one on the right belongs to the new Guide Ultimate. To make further reductions in the running temperature, engineers significantly increased the size of the pad pocket. You can barely make out the heat shield at the very upper part of the pad pocket. Between the new pistons, heat shield and wider opening, SRAM claims that the Guide Ultimate runs cooler than a Shimano XTR brake with both Ice-Tech and Freeza technology.

To simplify the bleeding process, there’s a new bleed port interface, with a new tool. The tool snaps into place and is held securely with a snap ring and rubber seal. After the connection is made, turn the knob counterclockwise to open the system for bleeding. There’s also a redesigned fluid path that allows bubbles to move through the system without getting caught up–as long as you have the pistons pushed back in, that is. To help remind you to do this, SRAM put the bleed port on the inside of the caliper so that you have to remove the wheel in order to do a bleed. Not only will it remind you to reset your pistons prior to bleeding, it’ll keep brake fluid off your rotors.

Here’s the bleed adapter locked into place.

To round out this new flagship stopper, SRAM will be offering two-piece Centerline rotors in both six-bolt and Centerlock mounting and in 140-, 160-, and 180-millimeter diameters. They’ll retail between $72 and $78.

And from the side.

Circle City Bicycles and Fitness

5506 Madison Ave.

Indianapolis, IN 46227

(317) 786-9244