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So far it’s a solo ride.

Factor Bikes OSTRO Gravel

Factor Bikes OSTRO Gravel

The Factor Bikes OSTRO Gravel

Mud be damned. Read more

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Factor Bikes OSTRO Gravel
Factor Bikes OSTRO Gravel


The OSTRO Gravel is a high-performance aero gravel bike designed for speed and versatility on mixed terrain. It features aerodynamic tube shapes, generous 45mm tire clearance, and a lightweight yet robust frame, making it ideal for gravel racing and off-road adventures.

In short, it's a bike built to win on any less-than-pristine surface, should you have the will. Or the legs. 

Factor's thinking behind the OSTRO Gravel's sculpted (but very tasty) lines is that gravel racing is often as fast as road racing. Perhaps not at Unbound's muddier editions, but give the OSTRO its head on a plunging fire trail or forest singletrack, and you'll soon see Factor's point. Gravel racing is getting really quick, and, as we all know, to finish first, first you must be fast. Or something like that.

To weave its way through the wind, Factor spent a lot of time on the OSTRO Gravel's head tube, where an all-new tube shape unlocked significant drag reductions by manipulating the 'laminar separation bubble' that occurs near the front of airfoils at lower speeds. According to Factor, the tech is rooted in aerospace. However, Factor assures us that all we need to know is that the OSTRO Gravel will get to the finish line faster and by minutes, not seconds.

With those muddier editions of Unbound in mind, Factor is also keen to reassure that the OSTRO Gravel's 45mm tire clearance is as-measured, with 4mm clearance either side in accordance with ISO standards. And that means mud won't stop the party. You may still cry. But at least your wheels will be happy.



Ordering Process

  • One of the lightest gravel frames on the market 
  • Real-world gravel aero
  • Generous 45mm tire clearance 
  • Built with Factor's 'win everywhere' mentality (only applies when you're on the bike)
  • Peerless handling 
  • Does party-pace and paceline in equal measure
  • Frame: TeXtreme®, Toray®, Nippon Graphite® Pitch-Based Fiber
  • Fork: OSTRO Wide Stance Fork
  • Seatpost: 0 and 20mm setback available
  • Bar/Stem: Black Inc Integrated Aero Barstem Reach 80mm, drop 120mm. Multiple stem lengths and bar widths available
  • Headset: CeramicSpeed SLT 1.5″ bearings
  • Head Tube Diameter: 1.5″ upper and lower
  • Saddle Rail Clamps: 7x7 and 7x9
  • Bottom Bracket: CeramicSpeed T47A Aluminium cups / CeramicSpeed bearings available for DUB, 24mm, or Ultra-Torque
  • Cable Routing: Internal
  • Compatible Components: Electronic
  • Brake Type: Disc
  • Max Rotor Size: 160mm front & rear
  • Max Chainring: 52-tooth
  • Front Axle: 12 x 100mm thru-axle
  • Rear Axle: 12 x 142mm thru-axle
  • Wheel Size: 700c
  • Max Tire Clearance: 45mm measured
  • Weight: 950g
  • Warranty: Limited Lifetime Warranty

Whether you’re already set on a certain make and model of frame, or still have some questions about how to go about your build, drop us a line and we can talk through your options. From the first detail to the final finish, we'll help you dial in the perfect set up for your next dream bike.

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