New 2025 Trek Rail+ Gen5 on Test – Degraded?

With each new Bosch Performance Line CX motor generation, Trek launch a new eMTB. The 2025 update of the Trek Rail+ comes with more battery power and longer suspension travel, and also promises more fun in all conditions. But can it still stand its ground under the harshest conditions, or have Trek taken a step back with the latest generation?

For a long time, the Trek Powerfly was Trek’s quintessential sporty eMTB. But when the Trek Rail was launched in 2019, it took the top spot, and shortly thereafter, the Powerfly was relegated to a touring eMTB. For three years, the Rail held the top spot uncontested in the lineup, but then the Trek Fuel EXe and soon after the Trek Slash+ were released – two lightweight eMTBs that are designed for trails and downhill action. Does the latest 2025 Trek Rail+ face the same fate as the Powerfly? While there are definitely signs pointing in that direction, there’s also much that suggests the Rail+ remains a downhill performer.

The new 2025 Trek Rail+ features a completely redesigned carbon frame with an integrated Bosch Performance Line CX Gen 5 motor and 800-Wh battery. It rolls on a mullet wheel setup with a 29” wheel at the front and a smaller 27.5” wheel at the rear, with the suspension generating 160mm of travel at the front and rear. While they were at it, Trek’s engineers increased the rear travel by 10mm from the previous version. Our test bike, the Trek Rail+ 9.8 GX AXS T-Type Gen 5, tips the scales at 24.12 kg in frame size L and retails at €8,499. But what exactly do you get for this hefty sum?

What makes a Trek Rail a Trek Rail? The new Trek Rail+ 9.8 GX AXS T-Type Gen 5 in detail

What is it – a competitive all-rounder, a tamed downhill powerhouse, or just a potent tourer? We take a closer look at the 2025 Trek Rail+ from all angles, starting with the new frame design.

Notable: The downtube looks somewhat oversized against the other frame tubes, and the main frame looks slightly compressed overall. Instead of a traditional seat tube, the seat post is now inserted into a sort of saddle dome. At first glance, the new 2025 Trek Rail+ appears less aggressive than its predecessor.

First-world problem: Trek often sent their test bikes in a Project ONE color scheme – a premium finish with deep metallic tones or effect paints. Our test bike in the Deep Smoke color (dark gray with small white spots) blends in with our test bike fleet without making a strong impression.

Speaking of colors: The retro-style tan-wall tires are a matter of taste and may appeal more to mountain bikers from the early days than to younger generations. The standard rear fender, however, is a hit with us: While fenders are often frowned upon on sporty eMTBs, Trek’s custom solution blends in well with the overall look and gives a sturdy, high-quality impression.

Even more controversial than fenders are kickstands on sporty eMTBs. Here, Trek adds fuel to the fire by equipping the chainstay with a mount for a stand. If you’re planning on throwing the Trek down rowdy trails, you’ll probably forgo this option. However, if you wish to park outside your local cafe while sipping on a fancy cappuccino, it’s a pretty handy detail. The question remains: which target group and purpose is the 2025 Trek Rail+ 2025 aimed at?

Motor system integration on the new 2025 Trek Rail+ in detail

We already mentioned the “visually dominant” downtube. This is most likely due to the new Bosch PowerTube 800, the integrated battery with 800 Wh capacity. All new Rail+ variants are compatible with a smaller 600 Wh battery and the PowerMore Range Extender, but all come standard with the bigger 800 Wh battery.

To house it, Trek moved away from their classic RIB system with side-mounted battery removal (Removable Integrated Battery system; RIP RIB). With the new RIB 2.0 system, the battery is now removed from the bottom of the downtube. A 6mm Allen wrench is used to release the side lock on the down tube, giving access to the battery.

The charging port is positioned just above the motor on the seat tube. While it was beautifully integrated into the frame on the predecessor, with the charging port cover painted in frame color, the successor is a bit less detailed. The port now protrudes slightly from the side. At least the plastic cover is spring-loaded and snaps shut automatically, protecting the contacts from moisture and corrosion.

Regarding cable management, Trek clear up the cockpit and, in return, create more cable mess between the bottom bracket and the rear end. The drive system is paired with a Bosch Mini Remote on the handlebars, and a Bosch SystemController integrated into the top tube, while a SRAM AXS Pod controls the shifting via wireless signals. From the rider’s perspective, the cockpit looks clean. The rear brake line and dropper post cable are routed internally, and disappear into the frame through cable ports on the head tube.

Curiously, Trek use the main battery to power the GX AXS Transmission rear derailleur, saving the need to charge an additional AXS battery. Speed measurements are taken care of by an old-school wire sensor and brake disc magnet on the rear wheel, rather than Bosch’s valve magnets. As a result, several cables pass through the swingarm, making the non-drive side look a bit cluttered.

The Suspension of the New 2025 Trek Rail+

Now that we’ve looked at the rear triangle, we can discuss the rear suspension kinematics. Trek use their proven ABP system, a special kind of single-pivot layout with an additional bearing on the rear axle and brake moment support. While the new Trek Slash+ relies on an elaborate high-pivot rear end, the Rail+ sticks with its existing system. Although Trek’s Active Braking Pivot is by no means bad, high-pivot bikes are in trend, and even our editorial team can’t resist their appeal.

Over the years, Trek experimented with proprietary suspension components and technologies. On the new 2025 Trek Rail+, however, these have been replaced with off-the-shelf parts. Gone are the days of Thru-Shaft dampers and AirWiz pressure sensors.

However, this doesn’t mean that Trek wrote off the 2025 Rail+ as a downhill machine. Both the rear suspension and the FOX 38 fork generate 160mm of travel. Trek also allow you to install forks with up to 180mm of travel to unlock the full downhill potential of the Rail+ – which speaks volumes. On the lower shock mount for the FOX Float X shock, Trek also integrated a FlipChip into the frame. This allows you to change the rear suspension’s progression from 19% to 24%, making the 2025 Rail+ compatible with a coil shock.

The geometry of the new Trek Rail+ 2025 in detail

Trek installed a geometry FlipChip called MinoLink between the shock link and seat tube. This lets you adjust the seat angle, bottom bracket height, and head angle by half a degree and 6mm. Depending on the setting, the head angle is either 64.5° or 65°, steeper than the previous model. If you prefer a slacker angle, you can purchase separate angled headset cups from Trek’s online store, which allow you to adjust the angle by half a degree in either direction.

The Trek Rail+ is available in four sizes, S to XL. The smallest S frame rolls on 27.5″ wheels front and rear. There are no intermediate sizes like ML, which Trek offer for some of their non-electric bikes. This results in a significant jump in reach from 450mm in size M to 490mm in size L. Riders who feel most comfortable with a reach of around 470mm will need to adjust the cockpit with custom parts to either push the handlebars farther away or pull them closer.

Size	S	M	L	XL
Seat Tube	380 mm	410 mm	435 mm	470 mm
Top Tube	562 mm	591 mm	639 mm	670 mm
Head Tube	100 mm	100 mm	120 mm	145 mm
Head Angle	65.0°	65.0°	65.0°	64.9°
Seat Angle	75.3°	75.3°	75.2°	75.2°
Chainstay	446 mm	446 mm	446 mm	446 mm
BB Drop	12 mm	18 mm	18 mm	17 mm
Wheelbase	1201 mm	1229 mm	1277 mm	1313 mm
Reach	435 mm	455 mm	495 mm	520 mm
Stack	598 mm	631 mm	649 mm	672 mm

The Spec of the 2025 Trek Rail+

Depending on the region, the 2025 Trek Rail+ is available in many different configurations. In Germany, there are seven variants alone. Prices range from €5,499 for an entry-level aluminum model to €12,999 for the flagship model. Within the individual variants, you can also choose between Shimano or SRAM drivetrains and FOX or RockShox suspensions.

The spec variant we tested features proven FOX suspension components, a SRAM GX AXS Transmission drivetrain, and many components from Trek’s in-house brand Bontrager, including the Bontrager Line Comp 30 aluminum wheels and Bontrager Line Pro Carbon handlebars.

With their distinctive sidewall color, the new Brevard tires are supplied by Bontrager, too, and are intended to replace the outgoing XR5 and SE5 models. The tread pattern is very similar to popular rear tires like the Maxxis Minion DHR II. However, it remains a mystery why Trek decided to fit the same tire both front and rear. With the new Galbraith, Trek already have a tire in their portfolio that is set to succeed the SE6 and features a more open tread pattern. But as with all theories, we’ll give the Brevard a fair chance in our practical test to prove itself.

How does the new 2025 Trek Rail+ fare on the trail?

If you choose the 2025 Rail+ as a companion for long tours, you’ve made the right decision. The riding position is pleasantly upright and comfortable – as long as you don’t fall between sizes. Riders just under 1.80m tall choosing a size L frame will sit in a slightly stretched position. With 800 Wh battery capacity, even epic backcountry expeditions are an option. Thanks to the revised internals, the new Bosch Performance Line CX motor ensures a pleasantly quiet ride.

Uphill, the 2025 Trek Rail+ performs admirably as well. The Bosch Performance Line CX motor shows its strengths again: thanks to the sensitive sensors and powerful start-up behaviour, even technically challenging climbs are achievable. If you’ve installed the latest Bosch software update, the maximum output increases to 750W, while the maximum torque goes up to 100Nm. The new eMTB+ mode is particularly impressive because it regulates power delivery to the rear wheel like a sort of traction control, preventing the rear wheel from spinning out.

Riding downhill, the performance of the 2025 Trek Rail+ delivers mixed feelings. When rolling along smooth flow trails, the weight of nearly 24.12 kg is hardly noticeable. The bike responds to steering input eagerly and directly, leaving tire marks in tight turns. Handling is on the playful side, making the Rail+ feel more like a trail bike than a composed, heavy-duty downhill machine.

However, trying to launch the 2025 Trek Rail+ off kickers requires plenty of effort to activate the sluggish suspension and get the bike off the ground. Trek missed out on some fun potential in the overly damped chassis here.

When racing against the clock downhill, the 2025 Trek Rail+ can generate plenty of speed. However, once again, you wish the tired suspension would work more actively with quick consecutive hits, but you can get used to it. Also, every bump on the ground is accompanied by a rattling sound in the frame, though this can be ignored with enough willpower. Advanced riders, who are at their peak technically, physically, and mentally, and stay focused, will benefit from the precise handling.

And if you make a mistake and completely miss your line, you can still quickly throw the anchor and come to a safe stop. Although the CODE Bronze brakes are not SRAM’s top performers, they can be finely modulated thanks to the 220mm HS2 rotor at the front and provide plenty of stopping power.

Unfortunately, the same can’t be said for the new Bontrager Brevard tires, which, in our opinion, use a rubber compound that is far too hard. Whether on damp forest trails or dusty hardpack terrain, they tend to lose grip too quickly and provide less traction compared to competing tires.

To put the riding performance of the 2025 Trek Rail+ into perspective: For a full-power eMTB, the 2025 Trek Rail+ delivers solid fun on flow trails and shows strong resilience on challenging descents. However, when compared to the Trek Slash+, it can’t quite match up and loses the top spot within the company’s internal ranking.

Who is the new 2025 Trek Rail+ the right E-MTB for?

The Trek Rail+ isn’t just for tourers, even though it performs well on long discovery tours with a high trail percentage. It also offers plenty of reserves for those who enjoy tough downhill riding. However, to fully unlock the potential of the Trek Rail+, it requires – in addition to a tire upgrade – an experienced rider to really push the bike.

Conclusions

Trek haven’t downgraded the new 2025 Rail+ to a touring bike, even though it’s excellent in that role. It holds its own on flowing home trails and in technically demanding alpine terrain but doesn’t necessarily shine in these disciplines. However, the platform offers many ways to address these shortcomings. With the right suspension and tire upgrades, it could narrow the gap to the sportier Trek Slash+ and potentially vie for the top spot in Trek’s lineup again.

For more information, visit Trekbikes.com

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Words: Rudolf Fischer Photos: Peter Walker