There are few components on a mountain bike as important as the brakes, and even fewer that can have such a dramatic effect on your confidence.
I pitted TRP’s EVO Pro and Hayes’ Dominion A4 brakes against each other – two of the most popular World Cup-proven brands outside of SRAM and Shimano.
While both of the mega brands make excellent brakes, there are plenty of reasons you might want to shop elsewhere.
Brakes from challenger brands offer interesting tech, an alternate feel, and simply the chance to use something different, which will be a sufficient draw for many riders.
So which of these brakes came out on top? To find out, I fitted both to a Vitus E-Mythique LT 297 VRS enduro eMTB and hit the steepest, rowdiest testing tracks for a couple of months, swapping back and forth between them.
Hayes Dominion A4
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- Price: £239.99 / $249.99 / €265
- Weight: 349g (lever, caliper & 180cm hose)
- Rotor weight: 186g each
- Rotors tested: Hayes D-Series 6-bolt, 203mm
- Pads tested: Hayes sintered
- Brake fluid: DOT 5.1
- Adjustment: Tool-free lever reach; bite point
Hayes Dominion A4 details
The Hayes Dominion A4 brakes use a four-piston caliper, with each piston measuring 17mm. Hayes says this design is intended to give riders strong braking power and more control for trail, enduro, downhill and eMTB riding.
The caliper is cold-forged for strength and durability.
The brake uses DOT 5.1 fluid, which Hayes claims handles heat well, and Kevlar-wrapped hoses, which are intended to reduce expansion under pressure.
A feature called QuickBite² is designed to speed up the bedding-in process when the brake pads are new, especially when used with Hayes’ D-Series rotors.
The pads and rotors also have a Modal Resonance Cancellation (MRC) system, which Hayes says helps cut down on noise and vibration.
Hayes’ MRC design changes the way the rotor and pads are shaped and supported so they disrupt braking vibration frequencies.
By altering the ‘natural’ vibration patterns, the system is designed to stop them from building up into audible noise or noticeable feedback.
For setup, the Dominion A4 brakes have Hayes’ Crosshair Caliper Alignment system, enabling small side-to-side adjustments to the caliper position, which can make it easier to avoid rotor rub.
The brakes also use the brand’s Two-Stroke dual-port bleeding system, which the brand claims makes removing air from the brake fluid quicker and more reliable.
The lever includes tool-free reach adjustment, so you can change how close or how far the lever sits from the handlebar.
There’s also an adjustable dead stroke, set low from the factory for fast engagement, but adjustable with a 2mm hex key.
Hayes calls its lever feel system ‘LoFi’ (Low Input, High Fidelity), which is designed to give quick engagement, reduced pull force and predictable power.
The lever runs on sealed cartridge bearings for smooth movement and has a flip-flop design so it can be mounted on either side of the bar. It’s available in an ‘SFL’ (Small Finger Lever) version for smaller hands. Hayes’ KingPin pad retention system is used to hold the pads securely and increase stiffness.
I tested the brakes with Hayes’ 203mm-diameter D-Series rotors. The brakes weigh in at 349g (lever, caliper and 1,800mm hose) and the rotors 186g each.
Hayes Dominion A4 installation and bleeding
The Dominion’s bleed process relies on a dual-syringe method – similar to when bleeding SRAM brakes, where you push and pull fluid between the caliper and lever to remove any air bubbles.
Hayes uses DOT 5.1 brake fluid, which has a high boiling point to help minimise brake fade, but requires careful handling compared to mineral oil.
What’s different about the Hayes Dominion brakes is the caliper has two bleed ports, to help remove any trapped air inside the caliper to get a solid, air-free bleed. Hayes also claims the lever design minimises the risk of trapped air.
The caliper can be bled by itself using the two ports and the dual-syringe method. You can then bleed the whole system – doing this takes longer but can give you a better bleed.
Installing the Dominion A4 is simple, and Hayes ships the brakes pre-bled, so unless you need to cut the hose, you won’t need to bleed them right away.
I needed to shorten the hoses, so I performed a full system bleed once installed, rather than the caliper bleed. This process was typical of a standard brake bleed and didn’t take more time or effort to get a firm lever feel.
While the caliper has Hayes' Crosshair alignment, I didn’t need to use this to get the brake to run without rubbing. Still, it’s a nice feature to have.
The lever-reach adjustment is easy to use and provides a wide range of reach adjustments to fit most hands. I found the dead-stroke adjuster had a decent range of movement, although at its minimum setting, the free stroke is modest rather than short.
Still, getting the lever to a place that was comfortable to reach and provided a good bite point was easy.
Hayes Dominion A4 performance
Out on the trail, the Hayes Dominion A4s have been among the most predictable brakes I’ve ridden, with good power, control and reliability.
The first thing I noticed was the lever feel – it’s incredibly light and smooth to pull. This takes a short time to adjust to, but once it became the norm, it occurred to me that most other brakes are frustratingly stiff.
I really liked this light free stroke, with minimal effort required to pull the lever, which helps keep your hands relaxed on the bar.
Even with this light lever feel, once the pads contact the rotor, the lever feel is firm and reassuring.
There’s a sharp bite point, which has instant power, and while it’s aggressive, it’s not grabby or difficult to control.
The modulation is excellent – I could scrub off just a little speed with a featherlight pull, or I could dig in harder for full stopping force without it feeling overwhelming.
That balance between control and power made a big difference on steep terrain.
Brakes need to perform equally on mellower tracks. A sharp bite force can stall speed on flatter trails, lose traction quickly, or cause the bike to stand up quickly mid-corner.
The Dominion A4s manage this well, and I found I could easily control how much force I wanted to put into the brakes to dictate how I wanted the bike to behave, which instilled plenty of confidence in my riding.
Another bonus is the predictability of the brakes – the bite point never drifts and feels the same run after run.
This made it easy to trust the brakes when I dropped into steep sections, or when threading through technical lines. Fade was also non-existent when pushing hard on sustained steep slopes.
There has been minimal noise throughout testing, with none of the squealing that can kill confidence mid-ride.
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TRP EVO Pro
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- Price: £260 / $329.99
- Weight: 336g (lever, caliper & 1,800mm hose)
- Rotor weight: 236g each
- Rotors tested: TRP RS01E 6-bolt, 203mm
- Pads tested: TRP Blue resin
- Brake fluid: Mineral oil
- Adjustment: Tool-free lever reach & bite point
TRP EVO Pro details
The EVO Pro’s four-piston caliper is designed to pair with TRP’s 2.3mm-thick rotors. The thicker rotors are intended to increase strength, improve heat management and reduce the chance of warping.
The brake uses mineral oil rather than DOT fluid, which TRP claims offers reliable performance and easier maintenance.
TRP's Pad Activation Dial (PAD) is a key feature, with this tool-free adjuster changing the point in the lever stroke where the pads first contact the rotor.
You can set it to your preference for either a quicker bite or a longer, softer engagement.
The brake also has a separate tool-free reach adjuster, which enables riders to change the lever’s distance from the handlebar to suit different hand sizes.
Both dials are designed to be easy to operate without tools.
The lever blade has been designed to improve mechanical leverage. It’s shaped for control and comfort, and uses an internal bearing pivot to reduce friction.
The lever body is single-sided (similar to Shimano's), meaning there are dedicated left- and right-hand levers.
The hoses come pre-bled and use TRP’s ‘EZ Plug System’ to make installation quicker, especially on bikes with internal cable routing – this is a plug placed in the hose to stop the brake fluid from leaking out.
When setting up the brakes, you remove the EZ Plug before installing the hose into the lever. This helps preserve the factory bleed and minimises the amount of air entering the system.
A quick lever bleed is then all that’s needed to get going once fitted.
TRP designed the EVO Pro in partnership with World Cup downhill and enduro riders.
According to the brand, the aim was to produce brakes with high power, smooth modulation and consistent performance on long, steep descents.
I ran the brakes with TRP’s 203mm RS01E 6-bolt rotors. The brake (lever, caliper and 1,800mm hose) tipped the scales at 336g, and the rotor at 236g.
TRP EVO Pro installation and bleeding
Bleeding the TRP EVO Pro brakes proved straightforward, with the mineral oil less corrosive and easier to handle than DOT fluid.
The bleed procedure involves using a syringe at the caliper and a funnel or bleed cup at the lever, which is similar to Shimano brake systems.
The process pushes fluid and any trapped air bubbles upward into the funnel, which makes it easy to see when the system is fully bled.
Installation is one of the EVO Pro’s strengths. Thanks to the EZ Plug system, the brakes arrive pre-bled with the hoses sealed, so you don’t lose fluid as you install the hose through the frame.
If you need to shorten the hose, you’ll have to trim it and re-bleed, but the EZ Plug helps keep fluid loss minimal. I got away with just a lever bleed to get the brake set and ready to ride.
Caliper alignment is typical – there are no special alignment screws like Hayes’ Crosshair, so it takes some fiddling, but it wasn’t problematic.
Setup is easy too, thanks to the tool-free reach and bite-point adjustment. The range of adjustment at the levers is good, and there’s a noticeable change between the free-stroke adjustment that will help if you're looking for either a quicker pad contact or a more delayed response.
The brakes will fit a wide range of hand sizes, with a noticeable difference between the extreme ends of the settings.
TRP EVO Pro performance
On the trail, the TRP EVO Pros impressed me with their overall power, but they have a different feel compared to some of the hardest-hitting brakes.
The level actuation force is light and better than most brakes, with a smooth rotation, meaning I could keep a relaxed hand on the bar.
The lever feel when the pads contact the rotor is firm but not sharp – the initial bite is good, but not class-leading.
Where some brakes snap into the rotor right away, the TRPs take a touch more pull force before the pads grab. Once engaged, though, the power builds steadily and predictably.
With a firmer squeeze, there’s plenty of stopping force on tap, enough for long, steep descents and hard braking zones. The overall power is good, and the way it ramps up makes it easy to control speed without locking up – but if you’re used to a harder bite, you may notice the difference.
This helps on smoother undulating trails without stalling the bike's momentum, but to get that instant grab, you need a little more commitment at the lever to get the best out of the brake.
I liked being able to adjust both the reach and bite point without tools. This makes setting the brake up and any subsequent on-trail adjustments easy. Noise was minimal, too, which is always a bonus, so you can maintain concentration on the trail.
I was impressed by the brakes' consistency – even on sustained steep runs, the lever feel stayed the same, and there was zero fade or inconsistency throughout testing.
How do the Hayes Dominion A4 and TRP EVO Pro compare on the trail?
Out on the trail, both the Hayes Dominion A4 and the TRP EVO Pro offer solid stopping power, but they each have a distinct feel and character that can shape how a ride unfolds.
I’ve spent time testing both on a mix of technical descents, smooth undulating tracks and sustained steep runs, and the differences quickly become noticeable. Each brake is easy to get the lever set up, but the TRP takes the win for ease of installation, and tool-free reach and free-stroke adjustment.
Starting with the lever feel, the Dominion A4 is immediately striking. The pull is incredibly light and smooth, which means my hands stayed relaxed even on long rides.
Once the pads bite, the feel is firm and reassuring, delivering an initial bite that’s sharp and aggressive. The Dominion A4s are not grabby or twitchy, but have a responsiveness that feels almost instant, instilling confidence on steep corners or when threading through technical sections.
In comparison, the TRP EVO Pros have a softer lever feel. Its pull requires a touch more effort to reach the pads, and while the level actuation is smooth and comfortable, the initial bite isn’t class-leading. You need a firmer squeeze to engage their full stopping power, which you might notice on higher-speed trails.
When it comes to overall brake power, both brakes perform very well. The Dominion A4 delivers ample stopping force that feels immediate and predictable, while the EVO Pro builds power more gradually.
This gradual ramp-up makes the TRP easy to control, particularly on smoother undulating trails where you don’t want to stall momentum, but it requires a slightly more committed lever input on steeper, more aggressive terrain.
Modulation is another area where the two differ. The Hayes offers good control but with a light finger touch – you can feather the brake for small speed adjustments, or you can pull harder for maximum stopping force, all without feeling overwhelming.
This level of modulation helps when negotiating sections with little traction or entering corners at speed.
The TRP is still controllable, but the softer initial bite means you need to anticipate the engagement slightly more, especially if you’re used to sharper-feeling brakes. On long descents, though, the EVO Pro maintains predictable power, and I didn’t notice any fade even on sustained braking zones.
Fade resistance and consistency were strong across the board. The Hayes Dominion A4’s bite point never drifted, and the lever feel remained the same run after run.
The TRP, likewise, held up well under extended, aggressive descents, giving steady feedback and reliable stopping power.
On the trail, each brake has its own strengths. The Hayes shines in situations where more immediate, sharp braking is advantageous – such as fast corner entries and steep chutes when braking hard. Its light lever and stronger bite make it feel effortless to control speed precisely with minimal braking force.
The TRP, meanwhile, excels on trails that require gradual speed management. Its softer lever feel and ramped power allow you to scrub speed without jarring the bike or losing momentum, though it demands slightly more hand strength to reach full stopping force, but it’s not a deal breaker. The Hayes is just exceptionally light.
Overall, the Dominion A4 feels more aggressive and precise, rewarding riders who value instant bite and light lever feel.
The EVO Pro is slightly more forgiving and smoother, favouring riders who want steady, controllable power over raw immediacy.
Both brakes are quiet, consistent, and fade-resistant, making them dependable options, but the choice comes down to personal preference in lever feel, initial bite, and braking style. It's worth noting the Hayes is cheaper and lighter.
How we tested the brakes
I tested both brakes over several months on the front and rear of a Vitus E-Mythique LT 297 VRS – a 25kg enduro eMTB. This chassis gave the brakes the most demanding test rig to review their power, bite, modulation, heat resistance and reliability.
I installed the brakes myself, following the brand's online setup guides.
I cut the hoses to suit the required lengths, and bled them with the brand's bleed kits.
I routed the rear brake externally so I could swap both brakes easily.
Both brakes were used with specific 203mm rotors and pads, which each brand claims offers the most power. These were TRP’s Blue Resin pads and Hayes' Sintered Pads.
It was an exceptionally dry summer in the UK, so the brakes were tested mostly on dry, loose, and dusty trails, with the odd heavy downpour. However, they weren't tested extensively in prolonged wet conditions.
Trails ranged from smooth trail centres to full-on downhill runs and everything in between. Steep, tech, flowing and high-speed trails delivered a wide range of terrain to highlight where the brakes excelled and where they came up short.
Hayes Dominion A4 vs TRP EVO Pro bottom line
When it comes to choosing between the Hayes Dominion A4 and the TRP EVO Pro, both brakes are strong contenders, with interesting features and a different lever feel that you won't find from either SRAM or Shimano.
That's important, because brake feel is extremely subjective, so having options from smaller brands should be something we embrace.
In my view, the Hayes edges the TRP out as the better on-trail performer. The Dominion A4 combines an incredibly light, smooth lever pull with a sharp, immediate bite.
This makes it easy to modulate speed precisely, whether feathering the brakes through loose corners or digging in on steep technical descents.
The predictability is outstanding – the bite point never drifts, and the lever feel remains consistent run after run.
On long, sustained downhill sections, I never experienced fade, and the brakes stay quiet, which helps maintain focus on the trail. These brakes really inspire confidence in demanding terrain.
In short, the Dominion A4s feel more precise, responsive and confidence-inspiring on the trail, making them my preferred choice for performance.
The EVO Pros are a strong, reliable option for those who value ease of maintenance and a smooth, forgiving lever feel. Add in that the Hayes brakes are £30 cheaper, and these are the brakes I’d choose if I was spending my own money.
