When faced with the banning of computer-controlled active suspension, Formula 1 drivers of the ’90s wanted engineers to develop suspension that provided variable tuning without constant user input. While the possibility would have been taken as a joke in the ’90s, mountain bikers could also benefit greatly from suspension that delivers the damping we need at a moment’s notice. Trek not only teamed up with Penske Racing and Fox Suspension to make this a reality, but the company chose to release it on the highly anticipated 27.5-inch version of its most popular trail bike, the Trek Fuel EX.


The Trek Fuel EX 9.8 is made for the trail rider who gets out numerous times per week to ride with his buddies. It’s not a race- day bike designed to spit out podium finishes left and right, and it’s not a budget bike with a limited lifespan. It’s made for the rider who simply wants to have an absolute blast every time he rides his bike, regardless of conditions or terrain.


Time-tested OCLV Mountain Carbon is used in the frame and seatstays, while the chainstays of the Fuel EX 9.8 are aluminum alloy. Internal derailleur cable routing creates a sleek top tube, while carbon armor prevents a damaged downtube. Trek’s BB95 bottom bracket is designed to be stiffer than any other bottom bracket on the market. The combination of Trek’s Active Braking Pivot (ABP) technology, Full Floater shock mount, and magnesium EVO link give the Fuel EX 9.8 one of the most advanced rear- linkage designs currently available.


The Fuel EX 9.8 is the high-end workhorse of the trail fleet. Shimano XT, front to back, provides spectacular performance for a serious rider on the roughest trails without a price tag that merely shaves off a few ounces. Matching the versatility of the rest of the bike, the stealth-routed RockShox Reverb dropper post allows the rider to take full advantage of the bike’s ride-it-all nature with the simple push of a remote.


Moving out: While the Fuel EX has always been known as a do-it-all trail bike, the new 27.5-inch wheels make it even more capable of conquering the full gambit of trails and terrain. As we rolled out on our first ride, the momentum leaving the gate was enough to leave a lasting impression of how this bike rides.

Cornering: Ripping through corners, the lateral stiffness of the Fuel EX 9.8 rear end felt like that of a good ol’ Sherman tank, and we mean that in a good way. With the Bontrager Rhythm Comp wheelset, we were able to pick our cornering line with preciseness and exit exactly where we planned. Cornering consistency made this bike faster in the corners than any other section of trail. Its nimble nature left us flicking it from one turn to the next in hopes of never-ending berms.

Braking: The Active Braking Pivot suspension design on the Fuel lives up to its name and does an excellent job keeping the suspension active, whether or not you’re on the brakes. It’s so well-refined that the secret is to be gentle and let it do all the work. Using the brakes conservatively allowed the sticky tires and responsive suspension platform to grab on to every deviation in the trail surface without breaking loose.

Descending: The Fuel’s 13.1-inch bottom bracket height gave us the clearance we needed to avoid any pedal-jacking obstacles while still being low enough to keep our center of gravity where we wanted it. The Fuel EX 9.8 has no problem tackling any hairy sections of trail, but shouldn’t be relied upon as an aggressive descender. It’ll eat up all the mud and roots in its sights, but save the jaw-chattering minefield trails for something with a stouter fork and more aggressive geometry.

RE:aktiv: To get an accurate picture of how the new DRCV (Dual-Rate Control Valve) shock with RE:aktiv damping fared against its predecessor, we brought both along for our tests and swapped them out trailside. Running the same lines at similar speeds, we were able to compare the two on an identical playing field. We were able to crank out the ascents in the Fox CTD’s Climb mode without lost efficiency using both versions of the shock. Carving aggressive descents, the RE:aktiv-damped shock outperformed the DRCV shock in its ability to provide a stable riding platform that gave way to the necessary travel when faced with either low- or high-speed compressions. While many of the wreck- ing crew test loops contain miles of smooth and forgiving trail that’s easily ridden in the Climb mode of any suspension design, we’ve grown accustomed to tensioning up and bracing for impact when approaching a rocky section. With the RE:aktiv damping beneath us, we were able to pedal through flat sections on a stable platform with the confidence that the suspension would instantly transition to seemingly endless travel when rolling through rock sections or drops. Its colors shined through even more when embarking on rides dedicated to Trail mode. It offered optimal pedaling efficiency without any compromise in the reaction to low- and high-speed compressions.


The Fuel EX 9.8 may be oriented toward daily trail usage rather than all-mountain endeavors, but we still believe full-suspension bike design has reached a point where only cross-country-oriented bikes should arrive stock with an 80-millimeter stem. We dropped the stem down to 60 millimeters and found it put us in

a much more confident riding position. The factory setup places the brake and shifter between the grip and the remote lever for the RockShox Reverb post, making it impossible to reach without repositioning your hand away from a comfortable riding position. The fluid reservoir on the Shimano XT brake lever seems to reject being anywhere near the Reverb remote, but we were able to find a mediocre position for it between the brake and shifter.

While we consistently pedal size-large frames, the large (19.5 inch) Fuel EX 9.8 felt cramped while both climbing and descending. You’ll have to stop by your local bike shop to see what works best for you, but we’d prefer to go up a size.


The Trek Fuel EX 9.8 has years of staying power to prove itself as one of the most versatile trail bikes available. With the addition of 27.5-inch wheels and Formula One technology, it’s only got- ten better. The end result: Trek’s new Fuel EX 9.8 with RE:aktiv damping is no joke and is a truly well-rounded trail bike.



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