Mountain Bike Action Bike Test: Trek Fuel Ex Trail Bike

Trek Fuel Ex

Category: Trail
Suspension front/rear: 140mm / 130mm
Tire Size: 29″

Since its debut in 2005, the Trek Fuel EX has been a key player in progressing the evolution of mountain bikes. Its earliest iteration was drool-worthy, featuring quick-release axles, a 3x drivetrain and 26-inch wheels. Over its 15-year lifespan, the Fuel EX continues to push the progression of trail bikes and features a full redesign for its 2020 model year. The Mountain Bike Action crew was excited to once again reunite with an old friend and see what new tricks Trek taught this old dog. Here’s our full breakdown of Trek’s 2020 Fuel EX.

Increased suspension travel to the front fork makes the Fuel Ex more confident during descents.



Trek strove to increase capability while keeping the Fuel EX in the trail bike category. It meets industry demands by being longer and slacker without giving up efficiency for all-day excursions. The head tube is a degree slacker and the reach is now between 10mm and 20mm, depending on frame size.

Additionally, the seat tube is 1 degree steeper, which not only places riders in a better-seated climbing position but allows for deeper seatpost insertion, providing room for long-travel dropper posts.

The most notable change to the Fuel EX frame is an all-new downtube storage compartment nearly identical to the Specialized SWAT box. In our opinion, Trek better executed the locking mechanism but fell short with the opening, making it harder to fit everything you need. In order to get a tube, multi-tool, CO2 and inflator inside the frame, it must be tightly wrapped inside the supplied tool roll bag. A bonus feature of this system is that removing the trapdoor and placing it on your workbench makes swapping out bottle cages easier than ever before. The frame storage box goes unnoticed by most riders while ensuring they always have the items they need.


A SRAM Eagle, 12-speed drivetrain offers a wide gear range for conquering the trails.

The Fuel EX line offers a bike for every rider with multiple build packages to choose from. If that’s not enough, Trek sells Fuel EX carbon and aluminum frames for riders who want to add their own personal touch. With such a wide variety of build packages available, we recommend you cruise on over to Trek’s website to see all the models and color options available. There you will find an abundance of build packages mixing Shimano, SRAM, Fox and RockShox components.


The Fuel EX comes ready to rip the trails with Trek’s proprietary RE:aktiv Fox shock.

The Fuel EX started its life with only 100mm of travel and grew to 130mm in back. The 2020 model keeps the same amount of rear travel while bumping the fork’s travel up to 140mm. Although rear travel remains the same, the suspension didn’t go untouched. New for 2020 is a fixed lower shock mount coupled with a RE:aktiv Thru Shaft Fox shock. The new lower mount design is said to increase frame stiffness and increase tire clearance, making plenty of room for 2.6-inch-wide tires. Trek continues to use its Mino Link Flip Chips to offer riders fine-tune geometry adjustments.

Since the introduction of the Trek Fuel EX it has always been a bike built to shred.


Trek understands the needs of trail riders and strives to meet those demands with the all-new Fuel EX. While the bike has a laundry list of technologies that can be geeked out over, on the trail it’s a no-nonsense bike designed to charge the roughest terrain over and over again.


A good trail bike is one that strikes a balance between its ability to climb and its fun factor on the way back down. The Fuel Ex does just that. It’s a comfortable bike with a supportive suspension design and an optimized geometry, making it a pleasure to power up the trails. In comparison to the Top Fuel, which we recently reviewed, the Fuel EX feels less punchy, which is to be expected; however, in comparison to trail bikes in a similar travel category, it’s a standout performer.

Traction grabbing 2.6-inch wide tires make it easy to whip the Fuel Ex around turns.


Once we recovered from our charge up the singletrack, we prepared ourselves to take full advantage of the trails back down. Within the first couple of turns, the Fuel EX quickly proved it’s an all-new machine. The responsive handling is complemented by traction-grabbing tires that promote confidence that the bike will head wherever it’s pointed. Throughout our testing period, the Fuel EX soaked up every small bump with ease and provided all-day bottom-out support. We quickly found out that this Trek has the ability to get you out of any jam you might get into. Should you race an enduro on this bike? Probably not. But, you won’t be in over your head when the trails become difficult. The Fuel EX is a well-rounded shredder built to excel in any situation.


We’re often hard-pressed to bring you a list of upgrades for modern bikes, because the majority of these bikes are great right out of the box. It’s hard to pick apart bikes these days, other than commenting on small touch-point details like grips and saddles. Those parts are mostly subjective anyway, and a rider will need to determine what will or won’t work for him. The Fuel EX models are wisely spec’d, making them a great buy for anyone in the trail bike market.


Ever since the Fuel EX’s beginnings, it has positioned itself as a cutting-edge trail bike, and the newest iteration is no different. While the 2020 model doesn’t exactly break any new ground, it combines the best of what the mountain bike industry is already accustomed to. We thank Trek for not trying to reinvent the wheel, but instead looking for the absolute best way to pull the most performance out of it. The Fuel EX is a do-it-all trail bike built to meet the needs of trail riders everywhere.


Check Out Mountain Bike Action Magazine’s First Ride: Trek 2020 Fuel EX


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