SRAM Guide Ultimate Tear Down
When SRAM decided to completely revamp their brake systems, adopting a more traditional layout than their TaperBore™ Avid Elixir models, they released their multi-model Guide platform. The result was the most competitive, most interesting, and best performing (comparatively) trail bike binders they’ve produced since the original Juicy-7.
The SRAM Guide Ultimate master cylinder is differentiated by its slick carbon lever and Ti-hardware. Other key features, like the new architecture and bearing lever pivot, appear throughout the Guide brake line.
Compared to other trail-oriented brakes the Guide offers excellent modulation with an oh-so-smooth lever feel, truly usable pad contact and lever reach adjustments, comparable absolute stopping power, and a level of serviceability that is entirely uncommon with the current generation of brakes from other manufacturers.
Taking things apart with Jeff Bryson at .bikeroom.ca
In an era when, pads and hose fittings aside, most brakes are available in three parts (master cylinder/lever assembly, caliper, and brake line) the availability of small parts for Guides is impressive. In an effort to demonstrate how intricately serviceable these brakes are I partnered with Jeff Bryson from www.bikeroom.ca, a bicycle mechanic school in North Vancouver, BC, to do a full tear-down.
Getting ahead of myself: here’s the full system torn down to bits.
The Guide master cylinder assemblies differ only slightly between the different levels of brakes. This is a breakdown of a Guide Ultimate, but aside from the carbon brake lever and Ti-hardware, the basic architecture, and body, are shared throughout the product line.
Goodbye TaperBore™; hello SwingLink™ Catchy trademarked names aside, the more traditional plunger system is very reliable and the pivoting (SwingLink™) engagement offers excellent lever feel, and braking modulation, with drag free performance.
It wouldn’t be a SRAM product without a catchy trademarked name but, poking the Chicago Bears aside, the more traditional plunger system is very reliable and the pivoting (SwingLink™) engagement offers excellent lever feel, and braking modulation, with drag free performance. The linkage that engages the plunger, and is responsible for the huge – and entirely usable – range of reach adjustment, allows the pads to sit a reasonable distance from the rotor which makes for easier set-up and drag free performance. Unlike other systems that offer the same benefits, the Guide brake engages the rotor smoothly and consistently with no “clapping” or on/off feel.
Curved linkage attached to the lever blade engages the linkage the drives the plunger assembly. This mechanically increases the hydraulic force at the pistons.
Fluid transfer ports in the master cylinder: no re-inventing the wheel here, just a well thought out design.
The Guide calipers are also fully rebuildable. Music to the ears of anyone dealing with sticking pistons on a couple-year-old brake system with no recourse but for buying a new caliper. But this is one area where the brakes differ from model-to-model and probably, again blinging Ti-hardware and carbon lever blade aside, the best way to justify the top-end Ultimate stoppers to your significant other.
The Ultimate brakes feature a zero-loss bleed nipple at the bottom of the caliper that makes them significantly faster and more consistent to bleed. This means you can commit to more time for foot-rubs and/or household chores (whichever they find more enticing), at least until you have your new brakes mounted.
Fully rebuildable four-piston caliper. The u-shaped silver heat-sink helps cool separate heat from the pads and rotor from the brake fluid.
Quick connect, zero-loss, pro-bleed kit for Guide Ultimate. All Guide brakes are bled in the same way but the Ultimate is significantly faster to bleed.
Speaking of brake service and in this case service in general, I was most surprised by the lack of special tools required. Other than the bleed kit there are no proprietary tools needed to completely rebuild this system. This is where Jeff-the-Mechanic transitions to Jeff-the-Instructor with a quick reminder to familiarize yourself with the – readily available – tech manuals and service videos that SRAM publishes. There are some numbers, like the reach-adjust plunger position, which are important if you want your brake to perform as new instead of like poo.
No vice, press, or punch required. Taking apart the Guide brake is an entirely civilized affair.
Re-inserting the plunger assembly with a commonly available socket (it’s probably in your set). In addition to being a great mechanic and instructor I’ve heard Jeff is also pursuing a career in hand-modeling if any readers know of well-paying gigs.
BikeRoom Pro Tip #1: Read the instructions & watch the tech videos. Then get out calipers and do it right.
When assembling your brake it is a great idea to make certain that everything is well lubricated. Generally this extends to cleaning your pistons and applying some brake fluid (mineral oil for mineral oil ONLY systems // DOT fluid for DOT fluid ONLY systems — never the two shall mix). In the case of the Guide brake, where we have fully torn it down, Jeff recommends lubing all the seals/o-rings and the pistons with AGS Sil-Glyde. It has the same boiling point as DOT fluid and is friendly to the rubber bits, but it will stay in place much better during reassembly and in use.
BikeRoom Pro Tip #2: Sil-Glyde for DOT fluid brakes.
Aside from Magura’s classic closed-system HS series of rim brakes, SRAM/AVID is unique in their thread-in dual-syringe bleed that pushes fluid from a syringe at the caliper to a syringe at the master cylinder, where most systems just use a receptacle, and then can push the fluid back through the system to best eliminate any air bubbles that may be trapped. Like any system, this is an exercise in patience if you want to bleed your brakes right the first time. Jeff says that “bubbles are dicks” but the best way to deal with them is to “channel your inner-Canadian and ask them very nicely to come out.”
All the Guide brakes are bled similarly, but only the Ultimate model has the quick connect bleed fitting at the caliper. It makes a real difference in terms of speed and consistency of brake bleeds. Bleed blocks instead of pads. Bleed blocks are cheap and don’t mind a spill.
Syringe at the top. Pros where gloves when handling brake fluid.
Jeff patiently coaxing all the air out of the brake system: “Bubbles are Dicks, channel your inner-Canadian and ask them very nicely to come out.
In terms of raw stopping power, by appearance, the Guide is often compared, somewhat unfavorably, against other brands four-piston models. While this isn’t a review of the brake itself, I think it is prudent to note that it definitely isn’t fair to consider it against a Shimano Saint or Magura MT-7 brake, although it is often mis-spec’d into similar situations, when by weight-class it compares more directly to Shimano’s two-piston systems. With no inside knowledge, or access to a crystal ball, I’m excited to see the features of Guide system trickle up to a replacement for the Avid Code that I can only assume is in the pipeline. The same great feel and serviceability with more power? Yes please!
If you’re adept at working on your own bike, or just like the idea of a product that can be fully disassembled to replace individual parts, the Guide is a highly competitive trail brake with best-in-class serviceability that likely makes it worthy of your consideration.
Soap and water in a spray bottle are a great way to clean up when you’re done.
Want to give it a try?