Trek Fuel EX 8 29 review

A cross-country lineage doesn’t hold the Fuel EX back on the trail

Our rating 
4.5 out of 5 star rating 4.5
GBP £2,700.00 RRP | AUD $4,299.00 | USD $3,199.00

Our review

A direct, punchy feeling trail bike that just wants to go faster
Buy if, You like to mix big hills with plenty of fast, flowing trails
Pros: Well-specced, fun, agile and responsive trail bike
Cons: Heavier or more aggressive riders may want a stiffer fork and more progressive suspension, dropper post isn’t the best out there
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The Trek Fuel EX 8 29 is a bike with a lineage going back to cross-country racing. This DNA shines through, but without the drawbacks that this can bring — the Fuel EX is a genuine trail bike.

  • The Trek Fuel EX 8 29 is one of our Bike of the Year bikes for 2018. To read reviews of the other contenders and the categories tested across road, mountain and women’s bikes, visit our Bike of the Year hub.

Trek uses its ABP linkage design on this aluminium frame, with a rear pivot planted around the rear axle. This, combined with the custom RE:aktiv shock delivers a bike that not only climbs well, but can handle the descents too.

Trek’s Knock Block prevents frame damage from over-rotated bars, but makes bike storage a bit of a pain
Matt Wragg / Immediate Media

The RE:aktiv shock has an inertia valve inside it, which effectively gives an auto on-off pedal platform to prevent the shock from suffering too much influence from pedal inputs, while still remaining active on the descents.

In practice this works well, and it feels like there’s a subtle improvement in feel over some previous generations.

If you mash on the pedals you can definitely get the shock cycling through its stroke — it’s not a lock-out as such (there’s a low-speed compression lever for longer smooth climbs), but on pedally sections the bike feels very calm, composed and efficient.

While older versions had a slight clunk when the platform opened, the current generation is smoother, and there’s less of a noticeable feel when the platform gives way to the bike’s travel.

Fast-acting steering makes this a fun bike to ride
Matt Wragg / Immediate Media

Once in the travel, the Trek is relatively active, happy to sit into the travel, rather than on top of it. The Fuel EX doesn’t feel super at home on the steepest or roughest of trails, but with a cross-country heritage, this isn’t such an issue. 

Riders who want to get the most from the bike could add a volume spacer or two to the shock for more progression out of the back end, as the faster and steeper you go, the more the bike likes to find its way to the depths of its travel. It’s here that the bike also feels like it gets knocked around a bit, losing some of that sure-footedness composure it has elsewhere.

However, on the trails it’s most suited to, the ABP suspension does a great job. The rear wheel tracks the ground well, boosting confidence, partly thanks to the fully floating shock that’s bolted between the main swingarm and the rocker linkage. 

Trek’s ABP suspension linkage suspends the shock between the swingarm and rocker link
Matt Wragg / Immediate Media

Despite its 14kg weight, it doesn’t feel lardy and it’s happy to be lifted and placed where you want it on the trail. It is, in fact, better suited to a more refined, precise ride, rather than just being pummelled into whatever is in the way — it’s a bike that goes fast and rewards riders who are happy to place it where it’s needed. 

The frame, combined with the planted feel through the suspension feels like a solid, tight package too. It’s not flexing everywhere, but fortunately avoids feeling harsh, though the front triangle’s stiffness results in a definite accuracy as you guide it through the chop. Thanks to this it’s a fast, stable and fun bike that seems to want to accelerate everywhere.

The Mino Link allows a subtle geometry change, should you wish to switch from 29in to 650+ wheels
Matt Wragg / Immediate Media

Through the use of its Mino Link you can change the geometry of the Fuel EX, though I generally kept it in the ‘Low’ setting, best for the 29in wheels.

There’s room for 650b+ wheels in there too, and at this point it might be wise to switch to the high setting to account for the lower ride height given by plus-wheels.

Trek was one of the first to experiment with fork offset when it came to 29in wheels
Matt Wragg / Immediate Media

For £2,700 / $3,199 I feel the Fuel EX 8 29 is decent value for money. Trek uses a lot of its in-house Bontrager kit, and generally this is no bad thing.

The Line Comp 30 wheels don’t feel heavy or wooden and the cockpit is a decent shape (though I’d like a slightly wider than 750mm bar). The Line dropper post hasn’t proved the most reliable though, getting a touch sluggish in cold or grimy conditions.

Due to supply issues, the test bike came with Schwalbe Nobby Nic tyres, but Trek lists Bontrager SE5s as the stock tyre. I would like to ride the bike with the Bontrager rubber as the relatively hard compound Nobby Nics on the bike aren’t the grippiest and I feel I could get more out of the bike with slightly better tyres.

Despite cross-country roots, this is a bike that can handle air time
Matt Wragg / Immediate Media

Up front is a 130mm Fox Rhythm 34 fork with the Grip damper. This is the base model 34, but one that I’m rarely disappointed to see. Okay, the spring curve from stock is a touch linear, but add a volume spacer or two and it’ll ramp up towards the end of the stroke.

However, the feeling through the bar is smooth and composed, without the slightly harsh or spiky feeling other ‘budget’ forks can have. This year’s Performance and Performance Elite level Fox forks feel better than last year’s, but they don’t feel drastically better than the Rhythm 34s here.

SRAM’s GX Eagle is popular on bikes of this type
Matt Wragg / Immediate Media

SRAM’s Guide R brakes offer decent braking power for a bike such as the Fuel EX, and the GX Eagle groupset now has to be regarded as the benchmark trail groupset.

Trek also offers an XT 2×11 option for the same money in some territories, though I feel the GX Eagle is the one to go for.

Also consider…

If you’re looking for alternative options, have a look at the following list. Each bike has been thoroughly tested and robustly reviewed. Click on the links for the full review.


Product Specifications


Name Fuel EX 8 29
Brand Trek

Available Sizes 15.5in 17.5in 18.5in 19.5in 21.5in 23in
Seatpost Bontrager Drop Line
Wheelbase (in) 47.8
Top Tube (in) 25.04
Standover Height (in) 29.49
Seat Tube (in) 20.08
Chainstays (in) 17.01
Bottom Bracket Height (in) 13.54
Wheelset Bontrager Line Comp 30
Stem Bontrager Line 60mm
Shifters SRAM GX Eagle, 12-speed
Seat Angle 66.2
Brakes SRAM Guide R
Saddle Bontrager Evoke 2
Rear Tyre Schwalbe Nobby Nic 2.3"
Rear Shock Fox Performance Float EVOL Grip
Rear Derailleur SRAM GX Eagle, Roller Bearing Clutch
Head Angle 67.2
Handlebar Bontrager Line 750mm
Front Tyre Schwalbe Nobby Nic 2.3"
Frame Material Alpha Platinum Aluminium 130mm
Fork Fox Rhythm 34 130mm
Cranks SRAM Descendant 6k Eagle, 32T Direct Mount X-Sync
Frame size tested 21.5in