Trek TOP FUEL 9.8 AXS Gen 4 - Carbon Mountain Bike - 2025 - Matte Dark Web

Outstanding performance on the trail

The Top Fuel 9.8 GX AXS Gen 4 is a lightweight carbon trail bike built to rip up climbs and stay playful on descents. It gives you the confidence you want through roots and rocks, thanks to a 120 mm/130 mm RockShox suspension package with a Pike Select+ fork and Deluxe Ultimate shock. Plus, you can shift easy even under load with a SRAM GX Eagle AXS wireless transmission. 

Highlights of the Trek Top Fuel 9.8 AXS Gen 4 Mountain Bike

• Lightweight and stiff full carbon frame with integrated storage compartment.
• Other carbon components such as handlebars and rims keep the weight down.
• RockShox Pike Select+ suspension fork with 130 mm front travel.
• RockShox Deluxe Ultimate RCT shock with 120 mm of rear travel.
• Lightning-fast shifting is made possible by SRAM's 12-speed wireless electronic shifting.
• Wide Line Comp 30 wheels improve tire support so you can ride at lower tire pressures for more traction.
• The Rapid Drive hub with 108 teeth provides a deceleration-free power train.

Does my bike have a curved top tube?

On the smaller frames (XS and S), the top tube is curved. This design provides a lower standover height, which benefits smaller male and female riders when mounting and dismounting. The larger frames (size M and up) come with a straight top tube, as taller riders usually don't have a problem with the standover height.

Technologies of the Top Fuel 9.8

• Active Braking Pivot - allows Trek's engineers to fine-tune how the suspension responds independently to acceleration and braking forces. This gives you more confidence in critical situations.
• Uncomplicated cable routing - Thanks to rattle-free internal cable routing, the Top Fuel is quiet on the trail and easy to maintain in the workshop.
• ISCG- Mounts - ISCG-standard chain guide mounts make it easy to attach and adjust a chain guide.
• Bolted bottom bracket - are more robust than press-fit bearings, withstand the harshest conditions and simplify maintenance.
• Knock Block - Protects your frame when things don't go smoothly. The handlebar stop keeps your handlebars from spinning completely around in a crash to prevent too much pull on your lines and prevent handlebar contact with the top tube.
• Per Mino Link adjustable geometry - Adjust the steering angle (by 0.5 °) and the bottom bracket height (by up to 10 mm) by simply turning a threaded nut. Turn the threaded nut and choose between a flat and an even flatter geometry without compromising suspension performance. Another Trek exclusive technology.