FX Sport SL 4 is a carbon fibre 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.

*Please note – spec applies to all sizes unless listed separately

Frame: 400 series OCLV Carbon, internal routing, 3s chain keeper, DuoTrap S compatible, mudguard mounts, flat mount disc, 135x5 mm ThruSkew

Fork: Carbon, hidden mudguard mounts, flat mount disc, 100x5 mm thru-skew

Weight: M – 10.50 kg/23.15 lb

Weight limit: This bike has a maximum total weight limit (combined weight of bicycle, rider and cargo) of 136 kg (300 lb).

Shifter: Shimano CUES U6000 w/optical gear display, 10-speed

Rear derailleur: Shimano CUES U6000 GS

Crank: Prowheel alloy, 42T narrow-wide ring, 175 mm length

Cassette: Shimano CUES LG300, LINKGLIDE, 11-48, 10-speed

Chain: Shimano LG500

Pedal: Bontrager City pedals

Max. chainring size: 1x: 44T

Hub front: Formula CL-51 alloy, 100x5 mm

Skewer front: 135x5 mm bolt-on

Hub rear: Formula CL-52 alloy, 135x5 mm

Skewer rear: 169x5 mm bolt-on

Rim: Bontrager Paradigm, Tubeless Ready, 32-hole, 21 mm width, Presta valve

Tyre: Bontrager GR1 Expert, Hard-Case Lite, wire bead, 60 tpi, 700x40 c

Max tyre size: 42 mm without mudguards, 40 mm with mudguards

Saddle: Bontrager H1

Seatpost: Bontrager alloy, 27.2 mm, 12 mm offset, 330 mm length

*Handlebar:

Size: XS, S

Bontrager Satellite Plus IsoZone, alloy, 31.8 mm, 15 mm rise, 600 mm width

Size: M, L, XL

Bontrager Satellite Plus IsoZone, alloy, 31.8 mm, 15 mm rise, 660 mm width

Grips: Bontrager Satellite IsoZone Plus, lock-on, ergonomic

*Stem:

Size: XS
Bontrager Elite, 31.8 mm, Blendr-compatible, 7-degree, 90 mm length

Size: S, M
Bontrager Elite, 31.8 mm, Blendr-compatible, 7-degree, 100 mm length

Size: L, XL
Bontrager Elite, 31.8 mm, Blendr-compatible, 7-degree, 110 mm length

Brake: Shimano hydraulic disc, MT201 lever, UR300 calliper

Brake rotor: Shimano RT10, CenterLock, 160 mm

Rotor size: Max brake rotor sizes: 160 mm front and rear

We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colours, materials and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice. The prices shown are the manufacturer's suggested retail prices.

Weights are based off pre-production products at time of publication. Weights may vary in final production.

Colour Options:

Matte Onyx Carbon
Crystal White/Supernova

Fitness & Recreation

2026 Trek FX Sport SL 4