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If Trek launching a redesigned Top Fuel feels a bit like deja vu, we wouldn’t blame you. The company completely revamped its historically flagship XC race rig into a more playful trail-oriented bike just a couple years ago in 2019. For comparison’s sake, it took Trek 5 years to re-up its Slash model. This isn’t your glitch-in-the-matrix style of deja vu, though, yes the new Top Fuel shares a name with its predecessor, but its stance is quite different. This isn’t a minor revamp; almost every aspect of the Top Fuel has been tweaked in some way.
Starting with the numbers: This year’s Top Fuel gains a touch of travel in the rear, upping it from 115 millimeters to 120—ok, sure, not much, but it does now properly balance the fork travel, and suspension travel really isn’t the main story here. It’s the other numbers that make this bike far more interesting. This new Top Fuel almost completely sheds its traditional racing-geometry numbers to don a stance similar to, if not sportier than, its stonier sibling the Fuel EX. The headtube angle was slackened by a substantial 1.5 ticks bringing it to 66 degrees, while its seat tube was steepened to 76 degrees, and reach stretched about 10mm (the size large is 480mm) in the low setting. The steep setting adds about .4 degrees to these angles.
Aside from its numbers, the Fuel’s frame gains some major improvements and attention to detail. Taking some cues from the new Slash: the Knock Block is now upgraded to the 2.0 version (giving a 72-degree turning radius or the option to remove it entirely), the seat tube has been beefed up to the 34.9 diameter the bottom bracket is now threaded, and all frames in the range, aluminum included, now offer internal storage.
Additionally, the front triangle now sports fully-guided internal cable routing for the dropper post, shifting cables, and brake hose (mechanics rejoice), and the Mino Link geometry adjustment chips got moved from the seatstay pivots to the lower shock mount, making for a much simpler process to adjust the bikes geometry, and hopefully solving the issue of pivot bolts loosening up at the Mino Links.
On the suspension kinematics side of things, with the bump in travel comes a longer-stroke rear shock and the accompanying lower leverage rage, which should provide a bit more support for heavier riders. The shock also now uses a trunnion mount, which spins on bearings instead of bushings, which, on paper, should provide better small-bump compliance as well. The pivot placement was also tweaked slightly to provide a fairly flat anti-squat curve, which, according to Trek, should provide a very consistent and efficient pedaling throughout the bike’s travel range.
For the inevitable riders who want to get a bit more aggressive and slap on a bigger fork: Trek did validate this bike to work well with a 130mm fork. That will slacken up the Fuel’s angles by about half a degree all around.
Trek, true to form, is offering the Top Fuel in both aluminum and carbon models. The entry level Top Fuel 5 retails for $2,600 and sports a 12-speed Deore drivetrain, and a RockShox Recon Silver RL fork. At the top end, is the Top Fuel 9.9 XX1 AXS retailing for $11,000. Looking at the value props, the aluminum-framed Top Fuel 8 sits at $3,800 and rocks an XT drivetrain, 4-piston Shimano brakes, with a RockShox Sid Fork and the high-end Deluxe Ultimate RCT shock. Crazy for carbon? The Top Fuel 9.7 starts the range at $4,200, with a similar, though slightly downgraded spec to the Aluminum 8.