The Series One was the first frame when FITBIKECO started back in 2000 and it’s their most popular bike to date. For 2026 they've upgraded to a CNC machined Integrated headtube and a fully sealed bearing front hub. The S1 frame and fork has been lightened up and offered in 3 top tube sizes with corresponding handlebar and crank sizes.
- SERIES ONE (20.25 TT)
- FRAME: Cro-Mo Front Tri
- GEOMETRY: SERIES ONE
- HEADSET: Integrated w/Gyro Holes
- BB: Mid Sealed
- BARS: 2-Piece 8.7”x 29”
- FORK: Cro-Mo Steerer, 33mm Offset, Welded Insert
- STEM: FIT Top Load
- SEAT: More Padded Integrated Combo, 200mm Post
- CRANKS: Tubular Cro-Mo 160mm
- SPROCKET: FIT Key 25T
- PEDALS: FIT PC
- FRONT WHEEL: FIT S1W Rim w/Sealed Hub
- REAR WHEEL: FIT S1W Rim w/Sealed 9T Cassette
- TIRES: FIT OEM 2.4”
- BRAKES: U-Brake w/Low Tension Springs, Two Finger Lever, Linear Cable
- MISC: Sealed Front Hub/ Integrated HT New for 2026