the Hook EXT

...takes 'road-plus' further off the beaten track and sets the benchmark for a steel gravel bike.

"CX/gravel geometry with clearance for bigger knobby mountain bike tires, something gravel racers have long dreamed of."

Introducing the Hook EXT

Designed to run on 27.5” rim (though 700s work just fine) and using a wider tire produces a wheel with the same outer diameter as a typical 700x28c. This means it’s possible to run bigger knobby mountain bike tires, with all the grip they offer, yet retain the geometry of a CX/gravel bike, something gravel racers have long dreamed of. This is made possible thanks to a specially designed frame that utilizes a wider bottom bracket and yoke to maintain a wide yet short rear end. The Columbus Cromor double-butted tubing has the perfect blend of being lightweight yet durable, perfect for gravel riding. For 2018 the EXT features a new full carbon fork, with anything cage and fender mounts, creating more options for front end luggage. Additional frame features added for 2018 include the invest cast chain stay yoke, dropper post compatibility and direct mounts for top tube 'fule tank' bag. This versatile frame is designed to offer as much all-round use as possible, so if your journey is mainly on-road, swap out the wheels for a set of 700c’s, with clearance for anything up to 45c tires.


Frame updated with Bombtrack casted drive-side yoke, extra cage mount under down tube, direct mount top tube ‘fuel’ bag and stealth dropper post routing.

Columbus Cromor, double butted front triangle chosen for its lightweight yet durable properties ideal for CX and gravel rides.

Straight blade extra wide full carbon fork with triple cage mounts and 12mm thru-axle.

Clearance for 27.5 x 2.1" or 700 x 45c.



    COLOR 1: Matt Metallic Grey
    FRAME: Columbus Cromor double butted tubing,
    FORK: TORAY "T700/T800" Hi-Mod carbon TA disc fork, 1.1/8"-1.1/2" tapered, triple cage mounts
    HEADSET: FSA "No21/12/44" sealed a-headset, 1.1/8"-1.1/2"
    BB: 386 Evo, 86.5mm shell (not incl.)
    SEAT CLAMP: BT Bikes "Origin" Forged alloy
    WEIGHT: Frame 2545g (size M), Fork 505g (un-cut), H/set 100g

    CABLE ROUTING: external, hydraulic brake compatible
    BAND-ON DIAMETER: 28.6mm
    DROPOUT: invest casted 12mm thru-axle, flat mount disc, with repl. hanager
    EXTRA INFO: integ. fender and rear rack mounts, TT and under DT cage mounts, stealth dropper post compatible, invest casted chainstay yoke, fork with triple cage mounts

    Front: 650B x 54C

    700C x 45C / 27.5" x 2.2"

    Rear: 650B x 54C

    700C x 45C / 27.5"x 2.2"

    BRAKE TYPE: Flat mount disc F/R



      S M L XL
    Horizontal TT length (mm) 541 558 575 591
    Seat Angle (°) 72.5 72.5 72.5 72.5
    Head tube Length (mm) 110 131 149 169
    Head Angle (°) 70.25 71 72 72.5
    Seat Tube Length (mm) 510 540 570 600
    BB Drop (mm) 70 70 70 70
    Chainstay Length (mm) 425 425 425 425
    Fork Offset (mm) 48 48 48 48
    Trail (mm) 75 70 63.6 60.3
    Wheelbase Length (mm) 1010 1020 1027 1039
    Standover (mm) 765 790 815 840
    Reach (mm) 370 380 390 400
    Stack (mm) 544 566 587 608

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