MBA Bike Test: Trek Top Fuel 9.9

Trek Top Fuel 9.9

The recent introduction of the Supercaliber allowed Trek some room in its lineup to push the 2020 Top Fuel into a more aggressive cross-country category. The Supercaliber will likely be the weapon of choice for World Cup racers, while the new Top Fuel favors endurance racing with its increased travel and longer and slacker geometry. The Top Fuel is still a diehard cross-country bike but now offers a more relaxed attitude to make it, dare we say, more fun. This month the wrecking crew set out to see where the 2020 Top Fuel performs best.


Increased rider confidence was the main goal of the all-new Top Fuel, which offers a more trail-friendly geometry, allowing riders to take a relaxed approach down rough terrain. During long endurance races when riders can hardly see straight, the all-new geometry is sure to come in handy. The head tube angle is now 2.5-degrees slacker than the last generation Top Fuel in its low adjustable setting. The Mino Link, the chip that allows for its adjustable geometry, has been moved from behind the seat tube to the shock’s upper mount. Other changes from last year’s model include a steeper seat-tube angle for pedaling performance and longer reach across all frame sizes.

The Top Fuel got a straight-shot downtube and Knock Block system similar to what’s seen on its big brothers, the Remedy and the Slash. Cable routing was cleaned up from the last generation’s Top Fuel with an updated version of Trek’s Control Freak internal cable routing.


The Top Fuel lineup offers a wide range of prices, with the 9.9 model sitting near the top. Our test bike was armed to the teeth with high-end components, such as a SRAM XX1 12-speed drivetrain, a Fox 34 Step-Cast fork with 120mm of travel and a set of Bontrager carbon wheels and a carbon cockpit.

Carried over from last year’s Top Fuel is its Twist Loc dual-remote lockout. This handy grip-shift-style control allows riders to quickly lock out their suspension without removing their hands from the handlebars. Dropper posts are seen across the lineup, offering more control during rowdy descents.

The all-new Top Fuel received a relocated flip chip at the front of the rocker arm. 


Trek increased suspension travel from 100mm up to 115mm in back and 120mm in front. The additional travel places the Top Fuel in the endurance category, making it an ideal weapon for events like the BC Bike Race or Epic Rides series. The Top Fuel is still designed to be lightning-fast and efficient but offers more room for error during the latter half of a long, technical ride. Additionally, the on-the-fly lockout control gives the Top Fuel the ability to transform into a nearly rigid bike for blasting gravel roads.

Trek’s new Top Fuel geometry makes it more fun than ever during descents.


The Top Fuel gravitates towards a cross-country-style rider, but can also be well-mannered in the hands of a more aggressive rider. While the bike isn’t exactly made to take on jumps or drops, it sure doesn’t shy away from them. The added weight from its dropper post and heavier-duty suspension components will deter diehard racers, but weekend warriors and riders looking for a lightweight trail bike will fall in love with this new machine.

Increased suspension travel gives the latest Top Fuel a more comfortable ride


Trek optimized the Top Fuel for conquering climbs, and it showed during our testing. This bike rockets up the trails and encourages out-of-the-saddle climbing, thanks to its stiff and efficient pedaling platform. With the shock in the open position, we found traction easily; however, once we twisted the lockout switch, the bike became too stiff for technical singletrack. We reserved the lockout for smooth climbs and fire roads between trails.


Our test bike became surprisingly fun when the trails pointed downward. This lightweight shredder packs a punch well above its travel category and encouraged our testers to “send it” every opportunity they got. Thanks to the Top Fuel’s new geometry and dropper-post lengths that vary depending on frame size, this bike dices up corners with ease. The Top Fuel is the type of bike you can ride up and down the trail all day on without getting worn out. It blends efficient climbing with downhill prowess, making it an ideal machine for long days in the saddle or weekend races.


With the carbon wheels, Fox suspension and high-end SRAM drivetrain, there is almost nothing that needs to be upgraded on this machine. Out of the box, this bike is ready to go straight to the races or for a weekend trail ride. One thing that did catch our attention was the possible lack of grip options due to the twist-lock system. If you need new grips last minute, you may find yourself cutting or trimming a pair to fit.


At the end of the day, the Top Fuel is an excellent bike built to satisfy a wide group of riders. It’s not exactly a purebred cross-country bike, nor is it a full-fledged trail bike. It sits right in the middle of those two categories, pulling double duty as a legitimate XC race bike or a lightweight trail weapon. The rider most likely to purchase a Top Fuel isn’t afraid to shred singletrack in Lycra or catch a little hang time. If this sounds like your style of riding, you will be hard-pressed to find a better bike for the job than Trek’s all-new Top Fuel.


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