Trek Checkpoint+ SL 6 AXS Review

With its carbon frame, its TQ-HPR60 motor and a fully electronic SRAM transmission, the Trek Checkpoint+ SL 6 AXS embodies a particular idea of the high-end electric gravel bike. It claims a committed gravel endurance orientation, multiplies the mounting points needed for long-distance adventures and runs wider tyres. The observations below come from several outings mixing tarmac, tracks and forest trails.

First contact is immediate and unambiguous: the finish of the Checkpoint+ SL 6 AXS is absolutely faultless. Its two-tone paint, of irreproachable quality, does not go unnoticed; during rides, several passing cyclists took the time to turn round and look at it. The design is elegant and modern without falling into the visual overload that is so tempting in this category.

The OCLV Series 500 carbon frame, one rung below Trek's OCLV 800 Series, is carefully executed down to the smallest details. Cable routing is entirely internal and completely invisible from the outside. There is an integrated chain guard, concealed mudguard mounts and a UDH, or Universal Derailleur Hanger, standard that makes future transmission changes easier. A chamfered 142 x 12 mm thru-axle at the rear completes a coherent technical picture.

The fork is also carbon, with a tapered head tube and mounts for racks and mudguards. Combined with the numerous anchor points spread across the frame for triangle bags, frame bags and top-tube bags, as well as for front and rear racks, this makes clear that the Checkpoint+ SL 6 AXS is designed to head off loaded. It is a bikepacking machine that does not say so out loud.

One concession has to be accepted: this model is not strictly full carbon. The Bontrager Elite Gravel handlebar, the Praxis crankset and the Bontrager Paradigm Comp 25 wheels are aluminium, and purists will notice. In practice that changes nothing about how the bike rides.

It is on the transmission that the demanding positioning of this Checkpoint+ is easiest to measure. Trek opted for an entirely electronic SRAM group, built around Rival AXS E1 levers paired with a SRAM GX Eagle AXS rear derailleur of the Transmission type. That derailleur is normally the preserve of mountain biking, but Trek chose it here above all for robustness proven across every type of terrain.

The SRAM Eagle XS-1275 cassette, running 10-52 teeth across 12 gears, offers a 520 per cent range, enough to tackle a stiff climb as well as a long, gently rising drag at speed. The single chainring is limited to 44 teeth, consistent with the bike's gravel endurance vocation. A GX Eagle chain of the same Transmission type completes an assembly that inspires confidence before the rider is even in the saddle.

The Bontrager Paradigm Comp 25 wheels are tubeless ready with a 25 mm rim width. They carry Bontrager Girona Pro tyres in 700 x 42 mm, also tubeless. Clearance in the wheel arches allows tyres up to 50 mm without mudguards, or 42 mm with them, which leaves a good margin for anyone wanting still more comfort on the trails.

Braking is handled by 160 mm SRAM Paceline centerlock discs, compatible with rotors up to 180 mm if needed. The seatpost is carbon — a Bontrager unit in 27.2 mm with 8 mm of offset — an important point that separates this model from the range below. The Verse Short Comp saddle, 145 mm wide with steel rails, is perfectly acceptable. Finally, the TQ LED display, compatible with Bluetooth and ANT+, drives the whole motor system with a sober readout that stays legible in all conditions.

It was on forest tracks that the Checkpoint+ SL 6 AXS revealed its true nature. The OCLV Series 500 frame is a clear success: stiff, as it must be to return the energy put into the pedals faithfully, yet also able to absorb genuinely serious impacts. On one outing, a concrete block protruding some ten centimetres from a path was struck square at a good speed. It shakes, but the bike absorbs the hit without the slightest alarm and without any suspicious noise.

On a cycling circuit, the recorded testing reached 45 km/h on a gently descending drag, and held position within a group without difficulty on the rise, which is the advantage of an electric bike weighing only 13.81 kg. On paths strewn with gravel closer to small stones, and on sandy bridleways, the Checkpoint+ presses on with disconcerting assurance. Its gravel endurance geometry, with a slightly more upright posture than a road-focused machine, suits this mixed use perfectly. The rider is engaged forward in a tonic, energetic position without ever being folded double.

The IsoSpeed system, placed at the top of the seat tube, again proves its worth. By isolating the seat tube from the rest of the frame to allow vertical flex, it absorbs the inevitable vibration of rough surfaces without ever degrading stiffness or overall efficiency.

The SRAM GX Eagle AXS transmission delivers on its promises of robustness. Despite passages over broken-up tracks, a few jumps over unexpected obstacles and situations that could have unsettled a less well-designed system, there was not a single mechanical incident to report. Gear changes are crisp, precise and instantaneous. A double tap on the paddle, which drops several gears at once, adds extra fluidity to changes of rhythm. The 10-52 cassette genuinely covers every situation without exception.

The TQ-HPR60 motor is the direct and logical evolution of TQ's earlier HPR50 unit. With 60 Nm of torque and 350 W of peak power, against 250 W continuous, it advances on the two criteria that matter most while retaining its characteristic lightness at just 1.92 kg. Its harmonic pin-ring gearing guarantees compactness and near-absolute silence, and rides through woodland are not disturbed in the slightest by its operation.

Its behaviour in use is exemplary. The assistance engages with remarkable progressiveness and without the slightest jolt, which makes it feel natural and intuitive. On the steepest climbs it becomes genuinely precious: on the street reputed to be the steepest in Paris, at a gradient of more than 17 per cent, the recorded testing maintained a speed of around 17 km/h without ever straining.

The three assistance modes — Eco, Mid and High — are entirely customisable through the Trek Central application: maximum power up to 350 W, assistance level between 25 and 200 per cent, and an engagement speed ranging from progressive to rapid. There is one reservation, though: Trek Central remains functional, but its interface is seriously showing its age. In a field where every mobile application competes on modernity and ergonomics, this one feels like a survivor, and it is high time it was rebuilt to the standard of the bike it controls.

The 360 Wh TQ battery can look worrying at first sight, set against the 400, 510 or even 750 Wh found on some urban electric bikes. But applying the same reading to the Checkpoint+ SL 6 AXS would be a misjudgement.

The logic of this electric gravel bike is fundamentally different. Thanks to its low weight and the excellent efficiency of its frame, the rider most often exceeds 25 km/h, the speed beyond which assistance cuts out automatically. A good part of the time is therefore spent riding without electrical help, which radically transforms the energy equation.

A concrete example from the recorded testing illustrates the point: on an outing of around twenty kilometres mixing trail, city and road, with the motor set to maximum assistance throughout, 40 per cent of the battery's capacity was consumed. At that rate, 60 km is entirely conceivable in the same conditions. On a gentler profile and in Eco mode, the 80 km quoted by Trek looks perfectly realistic.

For the hungriest adventurers, Trek offers an optional 160 Wh Range Extender that mounts on one of the two bottle-cage positions and theoretically increases range by 44 per cent. It is a practical solution that avoids rethinking the silhouette of the bike. One last consideration is often forgotten: on a bike of 13.81 kg, running the battery flat is a far less dramatic adventure than it would be on a much heavier urban machine.