Trek Top Fuel 9.8 GX AXS on test: New Top Fuel - the high-end trail bike from Trek on test
Max Fuchs
· 26.09.2024
The Trek Top Fuel already has a long tradition - but not as a trail bike as we know it today. If you turn back the clock by three product cycles, you will find the bike as a thoroughbred race bike on the cross-country World Cup courses.
A lot has happened since then: in particular, Trek presented the Top Fuel in 4th generation has little in common with the former race bike. The key data: 130 millimetres of travel at the front, 120 at the rear, 29er wheels. So far, so good.
The facts about the Trek Top Fuel 9.8 GX AXS
- Price: 6999 Euro
- Area of application: Trail
- Frame material: Carbon
- Suspension travel: 130 mm front / 120 mm rear
- Wheel size 29-inch
- Frame sizes: S, M, M/L, L, XL
- Weight: 13.19 kg in size L (BIKE measurement)
- Weight of wheels: 5141 g
- Acceleration wheels: 4018 kg x cm² (BIKE measured value)
The 4th generation of Top Fuel - in love with detail & customisable
The geometry is where things get exciting. As the frame size increases, the chainstays grow in 5 millimetre increments from 435 to 445 millimetres. This harmonises the proportions of the rear triangle and main frame perfectly, even for extremely short or tall riders. In addition to the size-specific geometry, the Top Fuel also comes with all kinds of adjustment options. With just one flip chip on the shock mount, both the rear triangle progression and the geometry can be fine-tuned in two stages. Add to that the storage compartment in the down tube and a tool that travels in the thru-axle - the Top Fuel scores plenty of usability points.
The price: The Trek Top Fuel at a disadvantage
We don't really talk about money. But it is absolutely necessary when testing the Trek. Because the Americans are generally known for their high prices. This was the downfall of our test bike. With the 9.8 GX AXS model for € 6999, Trek only sent the second most expensive Top Fuel to the test, which is one of the cheaper bikes in comparison. As a result, the Trek is not yet fully equipped - in contrast to the more expensive competition. The price disadvantage is most noticeable in the wheels. Here Trek uses aluminium instead of lightweight carbon rims. This costs the US label important points in terms of weight and wheel acceleration.
Nevertheless, the candidate doesn't let up on the climbs and scores top marks in the Uphill classification. The riding position is perfect for climbing: neither too short nor too stretched and nicely centred. In addition to the balanced riding position, the low front end and long chainstays provide that mountain goat feeling. No ramp is too steep, no key section too difficult. The rear suspension works first-class: sensitive and very drive-neutral.
The features of the Trek Top Fuel 9.8 GX AXS Gen 4
- Fork / Shock: Rockshox Pike Select+ / Rockshox Deluxe Ultimate
- Gearing / Bandwidth: Sram GX Transmission / 520 %
- Brakes: Sram Level / 180/180 mm
- Wheels: Bontrager Line Comp 30
- Tyres: Bontrager Gunnison RSL; XT TR 29 x 2.40
- Seatpost / Stroke: Bontrager Line Dropper / 170 mm
- Max. system weight: 136 kg
- Guarantee: for life
- Special features: Storage compartment in the down tube, carbon handlebar-stem unit
A sporty playmate: the Trek Top Fuel downhill
Thanks to its long wheelbase, the new Trek Top Fuel can also cope well with high speeds. However, mastering steep descents with confidence was obviously at the bottom of the specification, if at all. The front is a little too low for that. The chassis, on the other hand, offers plenty of support and pop. In combination with the compact riding position, the bike invites you to play on tame terrain and responds willingly to the rider's impulses. Bunny hops over tree trunks, jumps over root fields or a small manual - the Trek does it all with ease.
However, as soon as the terrain gets rougher, the Ex-Racer reaches its limits faster than more downhill-heavy models. The rear suspension works well, but is stingy with its ability to swallow due to its short stroke and passes large chunks directly to the rider.
Trek Top Fuel 9.8: Lab results & BIKE review
Conclusion from Jan Timmermann, BIKE test editor
Although the Trek Top Fuel 9.8 is at a disadvantage in terms of price in this configuration, the concept convinced us. Thanks to the excellent climbing characteristics and the successful riding position, it is ideal for demanding and pedalling-intensive tours. Downhill fun is not neglected as long as the terrain remains tame and doesn't get too steep.
Max Fuchs
Editor
