SRAM G2 Ultimate: A Deep Dive

SRAM has long been a dominant force in bicycle drivetrains and, increasingly, braking systems. Their latest offering in the trail bike disc brake arena is the G2, with the G2 Ultimate sitting at the pinnacle of the range. The question on many riders' lips is whether this top-tier brake truly lives up to its 'Ultimate' moniker, positioning itself among the best mountain bike disc brakes available. We've taken a close look to find out.

Unboxing and Initial Impressions

Upon receiving the SRAM G2 Ultimate, we were immediately struck by the inclusion of the new stainless-steel HS2 disc rotors. These rotors are a significant departure from the standard CentreLine rotors, boasting a beefier 2mm thickness. This increased material, combined with a redesigned brake track engineered to enhance friction, and a distinctive grey, heat-dissipating paint on the recessed spokes, suggests a focus on improved power and heat management. SRAM claims the HS2 rotor can deliver approximately 7% more power than its predecessors. In theory, this could allow riders to opt for smaller rotors, thereby shedding weight without a compromise in stopping power. However, this enhanced performance comes at a cost, with HS2 rotors typically retailing between £50-£70 depending on size, pushing the total price for a complete G2 Ultimate brakeset well over the £700 mark.

Premium Features and Ergonomics

The substantial investment in the G2 Ultimate does unlock a suite of premium features. Expect to find stylish titanium bolts, a lightweight carbon lever blade, and the convenience of tool-free lever reach and bite point adjustment. While the dial for the bite point adjustment is indeed more user-friendly than on previous SRAM offerings, the contact point bezel remains recessed within the lever body, which can make fine-tuning a bit fiddly. As is customary with SRAM brakes, the lever clamps to the handlebar via a hinged clamp. This design often incorporates a pre-installed Matchmaker shifter mount, a thoughtful touch that helps to declutter the handlebars. While the setup process might require a bit of patience to manoeuvre everything into place, the payoff in terms of a cleaner cockpit is well worth the effort.

Engineering and Stiffness Advancements

Despite a visual resemblance to the older Guide brakes, and sharing the same pad shape and hose connections, the SRAM G2 Ultimate represents a completely new design. SRAM highlights stiffness as the primary area of improvement. The caliper retains its two-piece bolted construction, but modifications to the forging process are intended to make it more resistant to flexing under intense braking forces. This increased stiffness translates directly to a firmer and more consistent lever feel, a noticeable improvement that enhances rider confidence. The standard pads are the new Power Organic compound, featuring a steel (grey) backing plate designed to boost initial bite and mitigate brake fade. While these pads exhibited a slight tendency to squeal initially, they bedded in remarkably quickly, and pad wear has proven to be impressively durable, even when subjected to the rigil of wet and muddy winter riding conditions.

Pad Gap, Pistons, and Hose Technology

Further refinements have been made to the pad gap, with SRAM implementing changes to the machining around the pistons. This adjustment facilitates a drag-free setup from the outset and, crucially, the G2 is designed to maintain this optimal gap as the pads wear. This consistent pad gap ensures a more predictable and reliable lever feel throughout the pad's lifespan. Credit for this consistency also extends to the new phenolic pistons. These pistons, constructed from a resin-based material, offer excellent heat resistance and smooth actuation, reportedly allowing SRAM to eliminate the previous steel heat sinks that were previously employed.

Connecting the caliper to the lever is a new hose material. This hose features a smooth, matte finish and is claimed by SRAM to be more resistant to kinking than its predecessors. This improved durability is complemented by a slightly easier routing process when installing the brakes through modern bicycle frames.

Lever Feel and Weight Considerations

At the rider interface, the lever design remains largely familiar, retaining the comfortable profile of its predecessors. However, there are subtle enhancements, including additional machining around the master cylinder. The premium carbon lever blade, sealed bearing pivot, and the aforementioned tool-free reach and bite point adjustments are all carried over. In terms of weight, the new front brake, including the titanium hardware, tips the scales at 272g. This is actually 25g heavier than the Guide Ultimate brakes tested five years ago. However, the new two-piece CLX rotors (£68), which feature an alloy spider claw, help to claw back some of that weight difference. These rotors weigh 121g (for a 180mm size) and offer a respectable saving of 30-40g compared to a full steel rotor.

The New 'Power' Pad Compound

Perhaps one of the most significant updates, beyond the core brake architecture, is the introduction of the new 'Power' pad compound. This new compound is designed to bridge the gap between SRAM's existing sintered and organic offerings. Crucially, as it shares the same pad shape as the older Guide pads, it offers backward compatibility, allowing riders with first-generation calipers to benefit from this new compound. The Power pad is an organic compound with a grey steel backing plate, engineered to provide an improved initial bite and a more consistent power delivery during prolonged braking efforts, reducing the 'tail-off' often experienced.

Performance on the Trail

While many components have seen updates, the overall riding experience with the G2 Ultimate doesn't feel dramatically different from the already excellent Guide brakes. However, in a direct comparison, the subtle improvements are indeed palpable. The lever feels as though it has a stronger return spring, though SRAM states this isn't the case. This enhanced feel is likely a result of the advancements in the piston area. Once past the initial breakaway of the Swinglink cam, the broad, comfortable lever blades offer a delightfully light action. Power delivery is smooth and progressive, especially if you're accustomed to the more immediate, almost abrupt, bite of some Shimano brakes. As you increase pressure on the lever, resistance builds predictably at your fingertips, providing excellent feedback and communicating the exact amount of pressure being applied at the caliper. This results in superbly intuitive and natural modulation, with a tangible sense of solidity as hydraulic pressure builds within the system.

Once accustomed to this refined feedback, the new Power pads allow riders to brake later and with greater confidence. The brakes inspire trust, slowing the bike effectively from the moment the pads make contact with the rotor. Our testing involved rigorous use, with a set of rear pads being completely worn through. Despite challenging, wet, and gritty conditions, they demonstrated impressive longevity. Crucially, we experienced none of the inconsistent bite point issues that have plagued some of Shimano's XT and XTR rivals. A minor, yet appreciated, detail is the improved reach adjustment. The older Guide reach adjustment often felt gritty and unpleasant to use; the new system is crisp and precise.

Verdict and Comparison

The SRAM G2 Ultimate is undoubtedly a top-performing brake system, further enhanced by the aesthetically pleasing oil-slick bolts, giving it a desirable 'cool' factor. However, a couple of factors prevent it from achieving a perfect score. The considerable price tag is a significant barrier for many. Furthermore, SRAM's own CODE RSC brake offers comparable or even superior power, at a lower price point, and with equally attractive aesthetics. Therefore, while the G2 Ultimate might not be the 'ultimate' in terms of outright stopping power – a title arguably held by the slightly heavier Code model – it delivers a slick, dependable, and immensely enjoyable braking experience. Its refined modulation and consistent performance make it a pleasure to use on demanding trails.

Key Improvements Summarised

Frequently Asked Questions

Q1: Are the SRAM G2 Ultimate brakes significantly more powerful than the previous Guide models?
While the G2 Ultimate offers improved stiffness and a new 'Power' pad compound for better initial bite, the most significant power increase comes when paired with the HS2 rotors. The G2 caliper itself is designed for refined modulation and feel rather than a drastic power leap over the Guide.

Q2: Can I use my old Guide rotors with the new G2 Ultimate brakes?
Yes, the G2 Ultimate brakes are compatible with SRAM's CentreLine rotors. However, to take full advantage of the G2's potential, SRAM recommends using the new HS2 rotors.

Q3: How do the G2 Ultimate brakes compare to the SRAM CODE models?
The CODE models are generally considered SRAM's more powerful brake offering, designed for heavier-duty applications like downhill and enduro. The G2 Ultimate is targeted more towards trail riding, offering a balance of power, modulation, and lighter weight compared to the CODE.

Q4: What is the main advantage of the phenolic pistons?
The phenolic pistons offer superior heat resistance compared to steel pistons. This helps to maintain consistent lever feel and performance during long descents or repeated braking, and it allowed SRAM to remove the previous steel heat sinks.

Q5: Are the titanium bolts purely for aesthetics?
While the titanium bolts contribute to the premium look of the G2 Ultimate, they also offer a slight weight saving compared to steel bolts, further contributing to the overall performance package.