Trek 2026 FX Sport SL 4 Fitness Bike

1643-5323696

FX Sport SL 4 is a carbon fiber fitness bike for riders who want the speed of a lightweight road bike with the comfort and control of a flat handlebar. The 1x drivetrain simplifies shifting without sacrificing gear range, making this high-performance bike perfect for everything from solo workouts to speedy group rides.

It's right for you if...

You're ready to log big miles, and you prefer the feel of a flat handlebar to the drop bars that come stock on most road bikes. You prioritize comfort and performance equally, and want the simplicity a 1x drivetrain provides.

The tech you get

A lightweight 400 Series OCLV Carbon frame and fork, a Shimano CUES 10-speed drivetrain with a wide-range cassette, Shimano hydraulic disc brakes for all-weather stopping power, a lightweight tubeless ready wheelset, wide, fast-rolling Bontrager GR1 Expert gravel tires, and a vibration-absorbing handlebar and ergonomic grips.

The final word

Fast, capable, comfortable. FX Sport SL 4 has a road-smoothing carbon frame and quality parts that will hold up over serious miles, including the simpler-shifting 1x drivetrain.