SRAM’s New Guide Ultimate Brakes

It’s a year since SRAM released the Guide brakes, so it was about time they were given a bit of a re-vamp, so today SRAM is announcing the release the new Guide brake family. The 360g Ultimate has been seen on SRAM-sponsored bikes at the recent EWS round in New Zealand. There’s a completely new four-piston, S4 caliper, and a lever with SwingLink cam and carbon lever blades. It 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 aluminium piston interface for ease of setup and improved consistency, while Bleeding Edge technology makes bleeding Guide Ultimate “a quick and easy task.”

SRAM Guide Brakes

Available: May 2015

What’s new:
• S4 caliper
• Consistency and easy setup
• Heat management
• Bleeding Edge™ technology
• Carbon lever blade
• Titanium hardware
• Proven Guide lever design featuring Swinglink, Timing Port Closure
• Tool-free Contact Point and Reach Adjust
• Aluminum caliper and lever body
• Lever pivot bearing
• Compatible with current SRAM Guide brake pads
• Colors: Arctic Grey Ano and Black Ano
• Weight: 360g (front brake, includes rotor, hose, clamp, adapter and all bolts)

SRAM S4 CALIPER

The new SRAM S4 caliper features two pairs of unequally-sized pistons, improved bleeding, new seals and a new piston coating that’ll hopefully be UK-weather-proof. The new heat management system is said to run the caliper 20°C cooler than before.

They say:
• The all-new S4 Caliper features four machined and Moly-coated aluminum pistons for consistent rollback and easy set-up, improved heat management features and “Bleeding Edge” porting and adapter technology for easy bleeds.
• Pistons diameter: two 14mm and two 16mm pistons for power and modulation
• New seals, gland geometry and piston coating for improved rollback, results in easier setup and improved consistency.
• Heat Management: enlarged pad pocket, piston insulators and Heat Shield reduce operating temperature and minimize heat transfer to the caliper body.
• Bleeding Edge: new bleeding adapter and porting for quick, mess-free bleeding.

Centreline X Rotors

The new, lighter version of SRAM’s Centreline rotors, the X versions feature an alloy central carrier and a steel rotor.
Available: July 2015

Diameter: 140mm, 160mm, 180mm
Hub interface: 6-bolt, Center Lock
Aluminum carrier
Steel CenterLine brake track
Colour options (aluminum center): Black
Weight: 86g (140mm), 102g (160mm), 125g (180mm)

Buzzwords explained:

HEAT SHIELD
Aluminum heat shields breaks the thermal connection between the pad and caliper body.
Reduces caliper fluid temperature 
by about 20C even in the most extreme testing conditions.
Patent pending.

PISTON INSULATOR
Insulator integrated in the piston.
Phenolic pad interface: phenolic compound reduces heat transfer from the pads to the piston thus reducing fluid operating temperature.
Aluminum seal interface: consistent finish and reduced seal wear.

OPEN PAD POCKET
More air flow through the caliper to reduce heat:
Pad pocket is 2mm wider than the standard Guide caliper.
Pad pocket length is increased to expose full length of brake pads to air flow.

BLEEDING EDGE TECHNOLOGY
New bleed porting and fluid path make it easier to push fluid through the caliper for quick and easy bleeding.
Dedicated bleed adapter for the S4 caliper plugs into the bleed port and seals the system to minimize air contamination and fluid loss.

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