Just over one year ago, SRAM reworked their already phenomenal Guide brakes to create a top-level Guide Ultimate. It came with the all-new S4 caliper, which offered improved heat management, easier bleeding and even better performance. Now, almost all of those upgrades make their way down the rest of the Guide lineup.

With the Ultimates, the big changes to the calipers came in the form of alloy pistons, molded piston seals and more space for air to move around the pads. The Ultimate’s still rule the roost with aluminum pistons that are turned and then given radial grooves before being sent out for a moly coating. The grooves limit the piston’s ability to retract past the seal, helping it stay at the ready as pads wear. The rest of the line -Guide RSC, RS and R- will all have full phenolic pistons, but that’s the only feature difference between them.

Here’s how the rest of the upgrades make the line even better…


Fluid lines are machined into the caliper body, ensuring even pressure on each side of the brake. Both sides run from the hose, behind the calipers, and then directly to the bleed port, with minimal opportunities for air to get trapped along the way. The S4’s bleed port is at the bottom of the caliper and is now Bleeding Edge compatible for a very easy, one-way bleed.


The molded seals are better than a cut o-ring because they can better control the size and shape to have a tight fit inside the caliper body’s groove and a tight seal around the piston. Note how the seals in the pic looked curved; that’s because they’re stuck inside an angled groove that forces them to rest against the piston at an angle, which allows for better control over piston movement.


The S4 calipers have a larger, more open “pad pocket”, helping air circulate behind the brake pads and giving it larger exhaust areas. Pistons are 14mm and 16mm.


Lastly, the pads get a stainless steel heat shield at the front of the backer plate, putting an extra insulating layer between the hot backer plate/pad and the caliper body.

Functionally, the levers are the same, with different materials and adjustment options separating RSC from RS from R. But, all get a slight update with reach adjust improvements. SRAM says adjustment detents are much more positive, and it stays in adjustment even when the levers are pushed forward. The contact adjust mechanism’s materials are upgraded to feel smoother and remain easy to turn at the extreme ends of the adjustment range. The lever blade kit is backwards compatible, so you could upgrade the reach adjust if you already own a set of first generation Guides.


SRAM had the new Guide RSC laying around, so we weighed the rear brake in at 261g. It’ll also be available in polished silver. Pricing for the new Guide brakes are:

  • Guide RSC – $205 / €224 / £172 (reach & contact adjust, SwingLink, lever pivot bearings)
  • Guide RS – $154 / €168 / £129 (reach adjust, SwingLink, lever pivot bearings)
  • Guide R – $133 | €145 | £112 (reach adjust, DirectLink)

In addition to the alloy pistons, the Ultimate sets its self apart with titanium hardware and comes with their 2-piece Centerline-X rotor, and it’s available now. The RSC, RS and R will hit stores in June 2016.



  1. MikieG on

    I wish Sram would give up the brake market and concentrate on other things. It seams like the change from Avid is not a big change.

    • Dead on

      If they give up on brakes, then they can focus on front derailleurs… or improve on their excellent warranty department.

  2. M on

    I have to say, after pooh poohing Avid’s for so long, my Guide Ultimate’s are incredible. If the new iteration are just trickle down ultimate tech, that is going to be awesome for the consumer.

  3. Heffe on

    These are really fine brakes. If the cash ever comes available, I’d like to put the Level version on my hardtail as well.

  4. BILL on

    I for one have had no problems with Avid/ Sram brakes. I have a pair of Juicy 7s from back in the day and still believe they are one of the best brakes with the best lever feel. I have used other brakes, but still keep coming back to these.

  5. Antipodean_eleven on

    I still fail to understand how it is the bike industry feels the need to keep on ‘improving’ something like disc brakes. Can’t they, like the auto industry, just design them right the first time and move onto to other things… it’s not like hydraulic brakes are some sort of magical new thing, the technology and know how has been around for a very long time now.

    And yes, I think my XT’s are pretty darn good.

    • typevertigo on

      Just because it isn’t publicized doesn’t mean it doesn’t happen. With cars people are usually more obsessed with engine performance – brakes don’t really get a look in.

      I’m a retired time-attack car racer. Stuff like monoblock brake calipers and braided brake lines will help bring down lap time even with an underpowered car. The thing is, these were developed largely without much fanfare. Nobody understands the difference in performance between a cheaper two-part brake caliper and a monoblock one other than the price – because car brakes are hugely underappreciated and misunderstood, and everybody and their dog is just looking at engine tech.

  6. Colin M on

    @Antipodean_eleven totally agree. Mountain bikes are $3000 to $10000 now and at any level the brakes are prone to squealing, fade, and premature bleeds. It is laughable. I don’t think they have that issue with off-road motorcycles and the prices might as well be the same. Get a real brake company like Brembo or Nissin to make mountain bike brakes already.

  7. STS on

    And they still produce a brake with aluminum pistons? The piston is contacted by the fluid on its outer side and the hot brake pad on the inner side. Why would you use the metal with the best heat conductivity even if the piston only contacts the pad through a relatively “thin” circle? Other manufacturers have chosen other materials for their pistons a long time ago and it makes a difference.

  8. whobikes on

    Ha! Try to take a motorcycle brake and make it as light as a bicycle brake and see how easy it is to remove squeal, fade and premature bleeds. It’s pretty laughable to watch those “real brake companys” try.

  9. Colin M on

    @whobikes that is the issue for sure. Miniaturized moto brakes work only ok. They aren’t real brake companies, they are component companies that have a brake division. Magura seemed to have it figured out and then they went ultra weight weenie and they sucked. Now they aren’t even mentioned in the US anymore.

  10. Jeff on

    Why is it every time Sram shows a brake, we get those comments that they suck. Ok, Sram once had a problem with they’re brakes, I even had a couple of problems with them, but they are better now.
    Should we still be knocking Shimano for Rapid rise, Biopace or those terrible dual control levers? no, they moved from that, maybe some of you need to move away from the past with Sram.
    Sometimes I think they need to call this site, instead of Bike Rumor,” Bitch and spread rumors!”

  11. Bazz on

    I like my Guide RS brakes much more than any other Avid brakes I have ever owned.

    BUT If I had a choice I would still grab XT brakes any day.

    At least the Guide’s pistons have started sticking yet…

    3 months already? Time to bleed the Guides again.


COMMENT HERE: (For best results, log in through Wordpress or your social media account. Anonymous/fake email comments may be unapproved or deleted. ALL first-time commenter's posts are held for moderation. Check our Comment Policy for full details.)

This site uses Akismet to reduce spam. Learn how your comment data is processed.