SRAM Guide RSC Brakes

It’s no secret that Avid, SRAM’s brake department has been doing it tough for some time now. Go back a few years and their twin-piston Elixir models had all manner of quality control and bleed related issues. In some cases – especially on models with the in-line contact point adjustment – it was near impossible to get the last bit of air out. Aside from the problematic setup, the rotors often made ‘turkey gobble’ noises.

While these issues were present, Avid gained a lot of OEM spec on new bikes, so a large number of mountain bikers were exposed to these troublesome brakes. This left many mountain bikers feeling burnt and disgruntled, so the brand has a lot of catching up to do up before they regain widespread respect.

The last Avid brake that we reviewed was the X.0 Trail, and it was a big step up from the preceding models. The four piston calliper offered plenty of power and the first set that we tried was very quiet too. However the dreaded turkey gobble returned on our second set of X.0 Trails, so there was still work to do.

Even so, they were a damn sight better than any of the previous Avid models and I’ve had a set of X.0 Trails on my personal bike for the past 18 months. In this time they haven’t been bled and I’ve actually had more reliability issues with other popular brake brands.

SRAM NOT AVID! Now they’ve released a new model called the Guide. It’s been launched under the SRAM name in an effort to escape the Avid stigma. While the name is new, the four piston callipers carry over from the Avid X.0 Trails. The changes are in the lever and the rotor; both are totally redesigned.

Previously Elixir levers used a master cylinder design called ‘Taperbore’, a system that was unique to Avid. With a perfect bleed Taperbore worked swimmingly but any air in the lever would lead to inconsistent feel and performance—it wasn’t a very tolerant system if the bleed was off. The Guide reverts back to a more traditional straight walled master cylinder with a timing port—it’s a similar setup to most other MTB brakes.

While the lever blade is slightly shorter, the master cylinder body has grown in size when compared with to the Taperbore version. Overall the new levers are similar in size but they incorporate a larger fluid reservoir. This is supposed to improve consistency; both from a heat management perspective as well as providing a spot where any random air bubbles can hide without affecting the performance.

‘Deadband’ is the other new feature incorporated into the Guide lever. It is a cam that drives the pads quickly onto the rotor when you first pull the lever. They then change to deliver more leverage deeper in the stroke for when you really haul on the anchors.

With a more consistent and rounder shape, the Centreline rotors promise quieter running. They also have more steel in them than before, which is said to improve heat dissipation. The added material also makes them heavier; a 160mm Avid HS1 rotor was 95g versus 113g for the Centreline equivalent (and 133g versus 150g in a 180mm size). The new levers are heavier too; a front X.0 Trail was 229g compared to 260g for the Guide (lever, calliper and hose). All up the new system will add 100g to a bike when compared to the X.0 Trail brakes that they replace. To put this into perspective, they are now 10g heavier than Shimano XTR Trail brakes and 27g lighter than Shimano XT (based on the lever, calliper and hose, no rotor).

The Guides are offered in three flavours. The base model ‘R’ goes for $155 per end and has a tool-free reach adjustment but a regular pivot mechanism. Next is the RS; it runs the Deadband cam-style lever with a tool free reach adjuster ($180 per end). We tested the fully featured RSC; for $240 it features reach adjustment as well as a toolfree pad contact point dial that lets you finetune the free-stroke in the lever. These prices don’t include rotors, so add approximately $55 per end for the new Centreline rotors.

Given the trepidation that some have over SRAM/Avid brakes, we wanted to give the Guide some proper trail-time before writing this review. After all, some products work and feel great for a month, only to fall apart shortly thereafter.

Initially I found the power to be a bit off compared to the X.0 Trail brakes but it seems the Centreline rotors require a longer bed in period. After a week or two of riding, the brakes started to come on strong. Now it seems they offer as much or slightly more grunt than the X.0 Trail stoppers.

With the new cam actuated design, the lever has a different feel. It’s still very smooth thanks to the sealed bearing pivot but the action is much firmer when the pads first contact the rotor. While they have a more defined on/off feel, the modulation remains exceptionally good—a traditional strongpoint for Avid brakes.

GOBBLE BE GONE As for the turkey, well it appears that someone at SRAM ate it for XMAS dinner, as there were no gobbling noises from these brakes. I also fitted some Centreline rotors to the X.0 brakes on my hardtail and it’s now gobble-free too. In wet conditions there’s still a howl from the brakes when they are first applied but you’ll encounter the same thing with any brand of disc brake in the wet. I tried my review brakes on three different bikes and the result was equally smooth and quiet in each case.

To test their claimed resistance to air pockets, I initially cut and fed the hydraulic lines through the internal routing on my frame, reattached the hoses and hit the trails without bleeding. While I tried not to get air in the system, it was pretty much inevitable. Despite this, the brakes performed competently enough for the first month of the review; the imperfect bleed only became apparent under sustained braking where the lever pumped up and produced an inconsistent feel.

The bleed process for the Guide is identical to the outgoing Avid models. You need a proper Avid bleed kit with two syringes and a dose of patience. Personally I don’t think it’s a difficult job, it’s just one where you need to take your time and follow the steps as instructed (SRAM has a Youtube video that takes you through it). One bleed had the front brake sorted but my rear required two goes to get it right; quite understandable after passing the disconnected hose through the frame. They still aren’t as easy to bleed as Shimano brakes, but it’s not the sort of job that needs to be done too often—my Avid X.0 Trail brakes haven’t been bled in 18 months and they’re still going fine.

Are the Guide brakes the answer to SRAM’s braking woes? Well my experience suggests they had it 90% right with the outgoing X.0 Trail. Centreline rotors have (finally) silenced the brakes and for me the intermittent noise was the only real fault with the last generation of Avids. I took some time getting the bleed just right on my old X.0 Trail brakes and they didn’t give me any troubles. Of course it’s better to have a more tolerant system in case the bleed isn’t perfect, and it seems that SRAM has delivered on that front too.

With the idiosyncrasies seemingly sorted, we’re now left with an excellent brake for trail and all-mountain use. While they’ve gained some weight, they remain competitive enough for the gram counters. The lever shape is very comfortable with a smooth action and a nice ‘not too firm, not too soft’ feel. All of the adjustment dials on the RSC model are easy to use and they make a real difference. The modulation is brilliant and easily controlled, and when you do need to really haul on the anchors, the four-pot callipers are more than up to the task.

Hopefully the quality control is up to scratch and every set of Guide brakes works as well as these. If that proves to be the case, then SRAM will be well on the way towards redeeming themselves and they can certainly lay claim to making one of the best disc brakes on the market.

Monza Imports (03) 8327 8080 / www.sram.com