Why Top Fuel is joining TFR XC’s quiver

The Supercaliber is one of the most successful bike platforms in cross country mountain bike racing. Since 2019, it has won 26 World Cup races with Trek Factory Racing, eight World Championships, and an Olympic gold medal. So why, if given the chance, would you want to race anything else?

Trek Factory Racing-Pirelli XC staff and riders would have had the same question this time last year. But necessity is the mother of invention, and the team noticed a sneaky trend of increasingly devious World Cup courses, calling for more travel than the current Supercaliber platform allows.

Enter the Gen 4 Top Fuel, released in 2024. The 120mm travel mountain bike is billed as a “downcountry” rig, ostensibly putting it in a category just outside the lithe, nimble rigs that have traditionally dominated the World Cup circuit. That is, until gap jumps and ever bigger rock features entered the picture. Now you can expect to see Top Fuel being ridden wherever riders believe that its added capability gives them an edge, beginning at the first two World Cup rounds on a gnarly course in Araxá, Brazil.

To test Top Fuel’s application on World Cup tracks, Trek engineers and team staff constructed one of their own. A short loop was built in Durango, Colo., featuring big obstacles like what riders will be facing on the World Cup circuit’s most technical courses this season. First, the staffers rode the course, then TFR XC riders Riley Amos and Gwendalyn Gibson were brought in. Throughout testing, they rode Top Fuel and Supercaliber back-to-back, making sure that factors like wheels, tires, tire pressures, and drivetrains were kept the same between both bikes.

For every rider, Top Fuel was faster on the rough-and-tumble track. To confirm the findings, Evie Richards tested the bike in Europe, after she secured the second rainbow jersey of her career as short track World Champion aboard a Supercaliber. Once again, when faced with ultra terse, technical features, Top Fuel improved performance. 

So why is Top Fuel — a more stable, but notably bigger platform than the 80mm travel Supercaliber — the better option on rougher tracks? Efficiency, pure and simple. Greater suspension and a slacker geometry helps the bike chew through rough terrain, and make up the difference that it gives up to the Supercaliber on, say, steeper climbs.

It should be noted that Top Fuel wouldn’t even be an option if not for the game changing technology of RockShox Flight Attendant. The little black module attached to riders’ rear shock and fork automatically senses the terrain and adjusts the suspension between three settings: “Open,” for careening downhill through big impact rocks and roots; “Pedal,” to give riders the perfect amount of traction to power through tough trails; and “Lock,” which is the firmest setting for all-out efforts and smooth climbs. With Flight Attendant, riders never have to worry about getting stuck in a too-squishy suspension setting when it’s time to put the power down.

Supercaliber isn’t going away. The bike is simply too good not to stick around. And for less-chunky, more-climby challenges like Leogang, it’ll remain the weapon of choice. But for the burly beasts like Mont-Sainte-Anne, Top Fuel could be TFR XC’s podium machine.

“We look at it as we have two amazing bikes, and you get to ride whichever bike you want,” a Trek staffer said. “Our intention is to always give the riders the fastest race setup. It could be the Precaliber kids bike if that is the right bike for the course.

“Top Fuel is another amazing option. And we think we’ll see it more and more.”