PINKBIKE FIELD TEST
2020 Trek Top Fuel
The lightest bike in the Field Test might not be the most comfortable, but it packs a powerful punch.
Review by Sarah Moore & James Huang, Words by Sarah, Photography by Trevor Lyden
Trek wanted the 2020 version of the Top Fuel to be competitive, fast and lightweight, but more fun and versatile than the previous generation. Trek calls it a downcountry rig in their marketing copy, so we put it to the test in Pemberton, BC.
To accomplish their goals of making the Top Fuel more fun and versatile, Trek increased the rear travel from 100 to 115 millimeters, which is paired with a 120-millimeter fork up front. As for the geometry, the effective seat tube angle got a degree steeper, up to 75-degrees, while the head tube angle went from 70-degrees to 67.5-degrees. The reach is also a few millimeters longer, 440 on the size medium in the low setting.
Top Fuel Details
Intended use: Downcountry
Travel: 115mm (r) / 120mm (f)
Wheel size: 29''
Frame construction: carbon fiber
Head angle: 67.5° (Low)
Chainstay length: 435mm (Low)
Reach: 440mm (size Medium)
Sizes: S, M, ML, L
Weight: 26.1lbs / 11.8 kg (as pictured)
Price: $9,000 USD
More info: www.trekbikes.com
The Top Fuel continues to use ABP (Active Braking Pivot) suspension design. The design uses a pivot that rotates around the rear axle to keep braking forces from interacting with the suspension. The idea is that it prevents braking forces from affecting the shock. The big difference here is that the shock is now fixed to the frame, rather than sitting between the rocker link and the seatstays. The swingarm pivot has also ben moved forward, which Trek says helps the bike pedal better.
Also worth noting is that there is more room to run a dropper post. The size small frame can handle a 100-millimeter post, the medium can run a 150mm, and large fits a 170mm. Additional details include the Knock Block fork stop and down tube Guard, Control Freak internal cable routing and Trek's 'Mino Link' flip chip that allows the geometry to be changed from a low to a high setting. The Top Fuel is 1x only and will not accept a front derailleur. There are no ISCG mounts on the frame either, but you can run Trek's top-guide if you feel that you need that extra chain retention.
For the complete Top Fuel, the prices range from $3,299 USD for the aluminum Top Fuel 8 to $10,499 USD for the Top Fuel 9.9 AXS XX1 model. As tested, with a Fox Factory 34 Step-Cast fork, a SRAM XX1 Eagle drivetrain, carbon wheels, and SRAM Level Ultimate brakes, the Top Fuel 9.9 is $8,999 USD. It’s a Project One bike, though, so you have the option of customizing the components and colors for an additional cost. Climbing
Both James Huang and I found that the Trek Top Fuel had fantastic pedaling efficiency. The bike comes equipped with a lockout, and while it’s one of the best dual lockout systems we’ve used, there’s really no need for it. That efficiency didn't come at the expense of traction on the rough stuff either, and we were able to ride the Top Fuel up some pretty tricky climbs. That being said, while the bike was super efficient, that trait seems to have trumped comfort, and there's not a ton of small bump compliance.
Trek definitely made some compromises in ride quality to gain that efficiency with a digressive compression tune on the rear shock that’s hard to get moving initially. So while the pedaling efficiency is fantastic, we would like to see a slightly
more active setup in the open position, especially since that lockout is available. But as much as the rough ride could be a touch disruptive, the Top Fuel was still a killer climber even on the tech stuff.
The overall climbing position on the bike is good, if a touch short and upright, possibly because we are both on the taller side of the recommended size. As a result of that shortness, it was occasionally difficult to keep the front end on the ground on steeper climbs. The Top Fuel is quite nimble and maneuverable, and it was easy to navigate around tight turns and awkward sections of trail, unless you got stopped suddenly by the Knock Block, as James did on several occasions. Descending
On the descents, the bike bike feels shorter than its 440mm reach number would suggest, which means that extra attention is required to remain centered and in control. That being said, I found it pretty surprising what I could ride the Top Fuel down. It requires precision on every section, but it can manage pretty technical descents. It just feels like you're trying to get through whatever is in front of you piece by piece instead of flowing through the descent as a whole.
Unlike some of the other bikes in the test, the Top Fuel's nimbleness kept it on the more exciting side of nervous. While it was missing some small bump compliance, the mid-stroke was good and there was no harsh bottoming out on bigger hits which was impressive. It wanted to be pushed hard, and in the right hands it's a very capable bike.
Trek had the right idea with the components for this kind of bike. The Bontrager dropper works well and has 150mm of travel, and the Bontrager Kovee Pro wheels feel quite stiff and decently wide at 29mm between the bead hooks. However, the SRAM Level brakes don’t have a lot of power and aren’t very adjustable, the 750mm bars are too narrow. Cutting bars down is easy, so please give us 780mm at least—even on bikes like this.