Trek Fuel+ EX 9.8

Premium assistance without losing the trail-bike feel

The Trek Fuel+ EX 9.8 is for committed trail riders who want to add climbs and laps to a big day without the forceful character of a full-power e-MTB. Its TQ HPR60 motor provides 60 Nm and up to 350 W of peak power, so you still contribute to the ride while getting a useful lift on steep, awkward ascents. The carbon Fuel+ Gen 2 frame, capable suspension and powerful brakes make this a serious choice for technical singletrack, rather than a rack-equipped commuter or a low-cost introduction to e-bikes.

All current UK 9.8 builds pair that mid-power system with a removable 580 Wh battery. It is a particularly handy arrangement if the bike lives in a shed, shared hallway or anywhere without a socket nearby, as you can take the battery indoors to charge. The support is designed to feel quiet and measured rather than surging forward, which should appeal if you enjoy picking lines and working the pedals rather than simply pressing on.

Fuel+ Gen 2 is the current platform

The current UK model is Fuel+ Gen 2, available as XT Di2, mechanical XT and Eagle 90. Use Fuel+ Gen 2 plus the exact drivetrain name when comparing offers, as the three bikes share the OCLV Mountain Carbon frame and TQ system but have meaningfully different suspension, brakes and shifting.

In its standard EX arrangement, sizes M through XXL use 145 mm of rear travel, a 150 mm fork and 29-inch wheels front and rear. Size S is deliberately different: it has 150 mm front and rear travel, a 29-inch front wheel and a 27.5-inch rear wheel. That proportional mixed-wheel layout gives shorter riders more room to move behind the saddle, so it should not be treated as a smaller version of the full-29er setup.

The frame can be reconfigured between EX, MX and LX layouts, which is a genuine long-term advantage for an owner whose riding changes. It is not a quick wheel swap, though. A proper conversion needs the matching rocker link, lower shock mount, wheel and tyre, plus appropriate suspension parts. Changing rear-wheel diameter also requires retailer e-system calibration. A compatible 205 x 65 mm shock can take EX rear travel to 156 mm, but it does not reproduce the LX leverage curve on its own.

Choosing between XT Di2, XT and Eagle 90

The XT Di2 build is the polished electronic-shifting option. It combines Shimano XT Di2 with Fox Factory suspension, Shimano XT four-piston brakes and a factory-fitted TQ Smart Box for powered accessory integration.

The mechanical XT build keeps the Fox Factory suspension and Shimano braking package, but uses cable-actuated Shimano XT shifting. It suits a rider who values familiar mechanical adjustment and simpler trail-side servicing over electronic shift operation.

The Eagle 90 build takes a different route with mechanical SRAM Eagle 90 Transmission, a 10-52 cassette, RockShox Ultimate suspension and SRAM Maven Bronze brakes. Its Full Mount derailleur is rebuildable, giving it a practical appeal for riders who expect plenty of muddy miles and want a mechanical drivetrain with a wider cassette range.

The mechanical XT and Eagle 90 versions have the same official UK RRP, so this is primarily a choice of shifting feel, suspension preference and braking hardware rather than a simple value ladder. The detailed specification matters here, especially on demonstration or clearance bikes where an abbreviated title can hide the difference.

How the EX configuration should ride

With a slack, size-proportional chassis, stout 150 mm forks and four-piston brakes across the range, the EX should feel more like an involved trail bike than a heavy long-travel e-MTB. The suspension layout is intended to offer grip and control through repeated rough hits while retaining the responsive, all-round character of the EX configuration. It has credible technical-trail ability, but it is not presented as the longest-travel LX arrangement or a full-power uplift substitute.

Size-specific chainstay lengths help retain a balanced stance as frames get larger. The adjustable rocker and lower shock mounts also give the platform more future scope than a conventional fixed-layout frame. That flexibility is worth having if you genuinely plan to use it. If not, the standard EX setup is the sensible place to start because it is already the balanced all-round option.

Battery ownership and wet-weather care

A full charge of the removable 580 Wh battery takes approximately three to four hours. For longer trail-centre days or drawn-out moorland rides, a 160 Wh Range Extender is compatible with every frame size, but it is an optional extra rather than supplied equipment. A compatible 360 Wh battery can also be used with the required upper end-cap adaptor for a lighter setup.

Pedals are not included, so allow for suitable flat or clipless mountain-bike pedals when budgeting for a new bike. Regular wet-weather care is straightforward but worth doing: clean and inspect the chainstay guard, pivots, charging-port cover and drivetrain, and avoid directing high-pressure water at seals and bearings. The chain may contact the tall, replaceable chainstay guard in the 10-tooth sprocket by design; inspect that guard for wear, particularly after gritty winter riding.

What changed from the Fuel EXe predecessor?

Fuel+ Gen 2 is a substantial step on from the Fuel EXe platform. The newer bike uses the 60 Nm TQ HPR60 and a removable 580 Wh battery, where the predecessor used the 50 Nm HPR50 and a 360 Wh battery. Current 9.8 builds also have a colour display and the frame is designed around the EX, MX and LX configuration options. For riders coming from a Fuel EXe, the larger removable battery and broader frame adaptability are the headline changes.