We’ve been big fans of SRAM’s Guide Ultimate brake. There’s plenty of power, loads of modulation and the lever is highly adjustable. The thing that really set it apart from the rest of the range was the Ultimate specific S4 caliper, which used a number of tricks to improve heat management and consistency over the standard item.
The good news is that SRAM has now trickled down this technology to the rest of the Guide range. That means that even on the £112 / $133 Guide R, you’ll now get the same steel heat shield, insulated pistons and enlarged pad pocket to help keep things cool.
Another welcome feature is that the caliper now uses the Bleeding Edge design, which has a special sealing bleed syringe to try and prevent air from being introduced into the brake when connecting or disconnecting it.The caliper also has different internal porting to help ease fluid flow when bleeding, helping to reduce the chances of air being trapped in the system.
New gland and piston geometry also helps to ensure the pistons return to their starting position smoothly and accurately when you release the lever after braking. This not happening properly is the biggest cause of a brake having an inconsistent bite point, a criticism that could be levelled at some of the previous Guide brakes.
The final alteration to the Guide series is that the somewhat fiddly and rattly reach adjuster has been redesigned to be more positive feeling. SRAM claims the new design won’t creep due to vibrations over time. It’s also backward compatible to older levers, which we're sure will make quite a lot of riders happy.