I tested Nukeproof and Trek's aluminium trail bikes – and the winner is more engaging, capable and confidence-inspiring

The traditional trail bike feels as though it’s in a tight spot. Squashed from all sides by longer-travel enduro bikes that climb better than ever, increasingly aggressive cross-country machines and the unstoppable rise of eMTBs, the middle ground it once dominated has never felt more under threat.

What was once the default choice for riders who wanted to do a bit of everything now risks being overshadowed by more specialist bikes that also shine outside their specific discipline. The question isn’t only whether the humble trail bike still has a place in modern mountain biking, but what that place should be. That’s where these two bikes come in.

First up is the resurrected Nukeproof Reactor Alloy 290, returning with 140mm of rear-wheel travel, 29in wheels (you can fit a 650b rear should you prefer) and thoroughly modern geometry.

Priced at £3,999, the Reactor is pitched as a hard-hitting trail bike shaped by Nukeproof’s gravity-focused DNA. Stable reach figures, a slack head angle and a supportive suspension tune suggest a bike that needs to be ridden hard, not cruised around on.

Rider descending a rocky drop on a yellow Nukeproof Reactor Alloy 290 mountain bike — The Reactor Alloy 290 feels capable on technical features, with geometry and suspension that encourage aggressive riding. Scott Windsor / Our Media

Up against it is Trek’s latest Fuel EX 8 Gen 7 – a 145mm-travel trail bike that leans heavily into versatility and all-round usability rather than outright aggression.

At £3,200 in this build, it undercuts the Nukeproof on price, while offering one of the most adaptable frames on the market.

With a choice of leverage rates, rocker links and shock mounts, and compatibility with either 29in or 650b rear wheels, plus 60mm and 65mm shock strokes, the setup options are mind-boggling. For riders who like to fine-tune geometry, suspension feel and ride character, the Gen 7 offers a level of customisation rarely seen on a mainstream trail bike.

While the marketing narratives differ, these bikes have comparable travel figures, near-identical geometry numbers and a shared promise of true all-round performance.

Are they the final evolution of the traditional trail bike in a last attempt to defend the middle ground, or proof that the genre can still lead mountain bike design, rather than being pushed aside slowly by more specialised machines?

It’ll be interesting to see whether the trail bike will be the proving ground for ever more expensive, sophisticated designs in the future, or the category where trickle-down tech keeps the barrier to entry within reach.

Read more: Best trail mountain bikes 2026 – 20 the of the most exciting and capable MTBs ridden and reviewed

Introducing the bikes

Nukeproof Reactor Alloy 290

The Alloy 290 is targeted at riders who favour a more aggressive, performance-focused trail bike. It’s designed to thrive on faster, more technical trails and steeper terrain.

The spec pairs a chunky RockShox Lyrik fork and Super Deluxe shock with a SRAM Eagle 90 Transmission and Maven brakes, DT Swiss M1900 wheels and Schwalbe Magic Mary and Nobby Nic tyres, so it looks ready to be pushed hard.

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Trek Fuel EX 8 Gen 7

Trek’s Fuel EX is an all-round trail bike aimed at riders who want a bike for big days in the hills, technical singletrack and mixed terrain.

Its adaptable frame offers almost limitless geometry and suspension setup options, plus you can fit a smaller rear wheel if you prefer.

This build pairs a burly Fox 36 fork and Float X shock with a SRAM Eagle 70 Transmission and in-house Bontrager components throughout. It’s designed to be comfortable, confidence-inspiring and versatile.

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Nukeproof Reactor Alloy 290 vs Trek Fuel Ex 8 Gen 7 frame details

Close-up of Nukeproof Reactor Alloy 290 suspension linkage and carbon seat stays — The Reactor Alloy 290 combines an alloy frame with carbon seatstays, aiming to reduce weight while maintaining stiffness and durability in the rear end. Scott Windsor / Our Media

Both bikes are made primarily from aluminium alloy, but the brands take different approaches to achieve their desired ride characteristics.

Nukeproof uses a hydroformed 6061-T6 front triangle paired with carbon fibre seatstays, in a bid to keep weight and unsprung mass in check without sacrificing strength.

Trek makes the Fuel EX’s frame from its Alpha NEXT Platinum tubing, which is shaped carefully to add stiffness around the head tube and bottom bracket, while enabling more compliance elsewhere to help take the edge off trail chatter.

When it comes to frame features, both have all the modern trail-bike essentials. They share Boost 148mm rear-hub spacing, a BSA 73mm threaded bottom bracket and SRAM UDH (Universal Derailleur Hanger) compatibility, making wheel upgrades, drivetrain replacements and maintenance easier and cheaper.

Close-up of Trek Fuel EX 8 Gen 7 handlebar and cockpit with externally routed cables — Love the simplicity or loath the aesthetic: there's no headset cable routing on these bikes. Scott Windsor / Our Media

Cables are routed into the frame via the down tube, not the headset – a win for ease of servicing – while the generous chainstay and down-tube protection helps keep noise down and guards against trail abuse.

You can fit a full-sized water bottle inside the front triangle of each bike, too. The Fuel EX has integrated down-tube storage for tools or spares, while external accessory mounts are provided on the Reactor.

Nukeproof Reactor Alloy 290 vs Trek Fuel Ex 8 Gen 7 suspension

Both brands rely on proven suspension systems to control their 140 to 145mm of rear-wheel travel. Nukeproof’s four-bar, Horst-link design is effective, durable and tuned with hard riding in mind, using large-pivot hardware and sealed-cartridge bearings for longevity.

Trek’s ABP (Active Braking Pivot) setup, meanwhile, combines a single-pivot swingarm and linkage-driven shock with a pivot concentric to the rear axle. This helps keep the suspension active under braking, blending efficiency with stopping control, and enables a level of leverage-rate tuning that’s closer to that of a four-bar design.

Nukeproof Reactor Alloy 290 vs Trek Fuel Ex 8 Gen 7 geometry

Put the geometry charts side by side and it’s striking how similar these bikes are. While I tested a size-medium Reactor and a large Fuel EX, due to availability, there’s crossover in the key numbers, with the differences focused mainly on reach and stack height.

The medium Nukeproof has a 460mm reach and 629.26mm stack. On the large Trek, these figures increase to 485mm and 638mm – very close to a large Reactor’s 480mm and 638.29mm.

Both brands give their frames size-specific rear centres – 440mm on the medium Nukeproof and 442mm on the large Trek. Head angles are identical at 64.5˚ in their slack settings, while effective seat tube angles hover around 77˚, placing you in an efficient pedalling position.

Despite different actual seat tube angles – 70.5˚ on the Reactor and 72.6˚ on the Fuel EX – effective top tube lengths are closer than you might expect.

Bottom bracket height is one of the few clear differences. The Reactor sits lower, at 330mm in its low setting, compared to the Fuel EX’s 339mm, giving the Nukeproof a more planted, corner-hungry feel, while the Trek trades some of that aggression for extra pedal clearance on rough terrain.

Overall, these bikes are separated by subtle differences in suspension kinematics and ride height.

Nukeproof Reactor Alloy 290 vs Trek Fuel Ex 8 Gen 7 value for money

Close-up of Nukeproof Reactor Alloy 290 forks, frame, and suspension layout — The Reactor’s more sophisticated suspension helps deliver improved control and composure, especially when the trail gets rough or demanding.

Neither bike is cheap, at £3,200 for the Trek and £3,999 for the Nukeproof, but both builds offer solid value for money.

The Nukeproof edges it on suspension, boasting a second-tier RockShox Lyrik Select+ fork with Charger 3.1 damper and a Super Deluxe Select+ shock with external low-speed compression and rebound-damping adjustment. The Trek runs Fox’s more budget-friendly 36 Rhythm fork with GRIP damper, paired with a Float X Performance shock.

Both bikes use SRAM’s latest mechanical Transmission drivetrains. The Reactor gets the higher-spec Eagle 90 version, while the Fuel EX runs Eagle 70. Stopping duties are also covered by SRAM, with Maven Base brakes on the Nukeproof and DB8s on the Trek, each paired with a 200mm front and 180mm rear rotor.

Trek finishes its build with Bontrager components throughout, including Line TLR 30 wheels and Brevard Pro XR tyres. The standout feature here is the Rapid Drive 108 rear hub, with a fast engagement that adds a premium feel and improves technical climbing.

Close-up of Trek Fuel EX 8 Gen 7 rear hub and cassette with mud-covered drivetrain — The Fuel EX’s fast-engaging freehub helps deliver quick drive when you stamp on the pedals, making it feel more responsive out of corners and on technical climbs.

Nukeproof specs DT Swiss M1900 wheels shod with grippier, more supportive Schwalbe Magic Mary and Nobby Nic tyres – although the 15˚ engagement of the 370 rear hub feels slow in comparison.

Nukeproof Reactor Alloy 290 vs Trek Fuel Ex 8 Gen 7 ride impressions

Climbing

I ran the bikes with a trail-friendly 25% of shock sag, aiming for a balanced setup that would reflect how most riders would run them. It soon became clear that, while they sit in the same category, they ride very differently.

Despite the difference in frame size, the bikes felt surprisingly similar when I was in a seated pedalling position on climbs. That’s largely down to their effective seat tube angles, which differ by only 0.4˚. With the saddle set to the same height (measured from the bottom bracket), my hip position relative to the pedals felt similar on both.

In biomechanical terms, that means they feel as though they have similar seated pedalling efficiency. From there, though, the bikes’ ride personalities begin to diverge.

The Trek has a stable, composed pedalling feel, even as effort levels rise. On sustained climbs and long fire-road grinds, the chassis remains supportive, encouraging you to stay seated and maintain momentum, whereas on some bikes you have to continually shift position to keep it settled. Hit a technical climb, and the suspension remains active under power, absorbing roots and rocks.

This helps preserve grip and forward drive on awkward, stepped ascents where traction is at a premium. Combined with the quick-engaging hub, this makes it easy to modulate power and keep progress steady, even when cadence drops and timing becomes critical.

The Fuel EX’s upright seated position plays a big role in how comfortable it feels. Weight distribution feels balanced, front to rear, and despite the taller stack, feedback from the front wheel never feels vague.

Even when climbing seated on loose or technical ground, I wasn’t fighting to keep the front end planted. Over longer climbs and extended rides, this translated into less strain through my arms and shoulders, making the Trek feel less tiring over a full day.

Rider climbing a trail on a Trek Fuel EX 8 Gen 7 mountain bike — The Fuel EX pedals efficiently and is comfortable when powering up climbs. Scott Windsor / Our Media

On the Nukeproof, climbing feels more direct and purposeful. The seat tube angle places you comfortably above the bottom bracket, encouraging efficient pedalling. There’s excellent suspension support for the amount of travel, keeping the bike riding high in its stroke when you’re pushing hard on the pedals.

The biggest difference when pedalling these bikes comes from the Reactor’s reduced stack height and its lower-rise bar. This setup places more weight over the front wheel, and the pay-off is clear on steep, technical climbs. Front-wheel tracking is excellent, and wandering or lift aren't issues, even when gradients increase, or the trail becomes awkward or off-camber.

You can pick lines precisely and it’s easy to place the front wheel where you want it.

However, that lower front end also brings a compromise. With more weight carried through your hands and shoulders, the Nukeproof feels more physically demanding over longer rides.

The slower freehub engagement further separates the two bikes here, making slow-speed technical climbing and stop-start efforts feel clunkier on the Reactor.

Descending

When they’re pointing downhill, the contrast between the two bikes continues.

The Trek puts you in a stable, centred position when you’re standing up. Its taller front end provides confidence on steeper descents, helping the bike feel forgiving when trails drop away or when you misjudge a line. It’s easy to stay relaxed and let it do its thing, rather than feeling the need to manage body position continually.

The frame stiffness feels well-judged, with plenty of support when pushing into compressions or loading the bike through turns, but without the harsh, jarring feedback that can fatigue you on rough trails. This contributes to the Fuel EX’s easygoing nature and makes it well-suited to long days in the saddle and mixed terrain.

The Trek’s suspension performance is impressive for the price, too. On flowing trails and through medium-speed rough sections, it strikes a good balance between support and bump absorption, smoothing out chatter without blowing through its travel.

When the pace increases and the impacts get bigger, though, its limits become more apparent. On square-edged hits and through high-speed compressions, the fork and shock can spike and feel harsh.

In the corners, the Fuel EX’s taller bottom bracket height makes it feel slightly less settled in flat turns or high-load berms than the Reactor. Trek’s tyre choice compounds this – on wet or loose surfaces, grip is limited, and the sidewalls don’t provide enough support when you’re pushing hard.

Rider carving a berm on a yellow Nukeproof Reactor Alloy 290 mountain bike — The Reactor’s composed suspension and balanced geometry help it dig into berms with loads of grip and confidence at speed. Scott Windsor / Our Media

The Nukeproof adopts a more aggressive stance on the descents and its low bottom bracket creates a planted, secure feel through corners, encouraging you to lean the bike over and carry speed. It feels eager to be pushed harder, particularly on faster trails, where grip and stability matter most.

The frame stiffness is excellent and enables you to load the bike confidently without it feeling harsh. Meanwhile, the suspension delivers strong mid-stroke support while remaining active enough to absorb a wide range of bumps, giving the Reactor a composed and purposeful feel on the way down.

However, the low front end became more noticeable on steeper, more technical descents, where it demanded a more active riding style.

I had to stay engaged and deliberate with my body positioning, especially when terrain got steep, awkward or unpredictable. This will feel natural for riders who like a more aggressive stance, but it places more demands on technique and focus.

Battle of the brands

Rider descending a steep woodland trail on a Trek Fuel EX 8 Gen 7 trail bike — Despite its relatively affordable price, the Trek Fuel EX 8 Gen 7 can be pushed hard on demanding trails, staying composed and capable when the pace picks up. Scott Windsor / Our Media

The parts choices reinforce the brands’ different priorities. Trek has delivered a balanced, trail-focused build, with suspension performance that exceeds expectations for the price, plus a fast-engaging freehub.

While the SRAM Eagle 70 Transmission performs well overall, a few gears can grind under load in muddy conditions. Braking performance is adequate rather than exceptional, and the Bontrager tyres aren’t as good as the Nukeproof’s.

At £3,999, the Reactor comes with higher-quality and more downhill-focused components. Its SRAM Maven Base brakes deliver strong, consistent stopping power, and its Eagle 90 drivetrain shifts crisply and reliably, even under load.

The Schwalbe tyres offer a strong balance of rolling speed, grip and sidewall support across varied conditions, and the RockShox fork and shock provide excellent performance too. The slow freehub engagement affects technical climbing and acceleration, though.