FACTOR OSTRO Gravel

Lightweight Aero Gravel Bike

Every ride, whatever the surface, faster is what counts, and this is the gravel bike you’ve been waiting for.

OVERVIEW

The All-Road All-Star

The OSTRO Gravel takes its ‘win everywhere’ mentality from its road racer stablemate, the OSTRO VAM, and is likewise developed to dominate its category with incredible aero, superior handling, high stiffness and low weight. With a tyre capacity of 45mm, it’s ready to go anywhere, fast.

 

Gravel racing is fast and aero really matters, but it isn’t as fast as road racing so the requirements are different. The OSTRO Gravel frame is carefully optimised for the speeds at which you’ll be riding.

Attributes

AERODYNAMIC

LIGHTWEIGHT

COMFORT

CLIMBING

Terrain Mix
MOUNTAIN
20%

ROLLING
40%

FLAT
40%

All-Roads

The steering geometry on the OSTRO Gravel is optimised for all tyre sizes, this results in a fast-handling gravel bike on 43mm tires and an equally satisfying and precise all-road machine on 32s, with no low-speed wheel flop.

fitting

Let us help you find your size and dial in your fit

We offer a state-of-the-art bike fitting service from our Experience Centre, using the idmatch system. We can also assist remotely to give you a recommendation.

bike

Exclusive UK Partner

We are the exclusive UK partner for Factor Bikes & Black Inc and the only place to experience both brands.

Mechanics Icon_Black

Our mechanics build your bike in-house in Norfolk

Your new bike will be assembled by the skilled technicians in our Experience Centre in Norfolk. It can be delivered straight to your door or you can collect it for a New Bike Day experience.

DESIGN

AERODYNAMICS

Factor’s engineering teams developed the OSTRO Gravel using a ‘zoned aero’ strategy. This meant they focused the front of the bike on aerodynamics because that is where it meets clean, or freestream, air flow. At the rear of the bike the air flow is too chaotic so the focus was ride quality and lightness.

In particular, a lot of time was spent on the 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. The tech is rooted in aerospace but all you really need to know is that the OSTRO Gravel will get you to your finish line faster, and by minutes, not seconds.

Build My OSTRO Gravel

BLACK INC COMPONENTS

Factor’s OSTRO Gravel is equipped as standard with a flared Black Inc Aero Integrated Barstem, available in a wide range of bar widths and stem lengths, starting at 36cm wide up to 42cm, with stem lengths from 80mm up to 140mm. The new barstem has undergone rigorous CFD and wind tunnel testing and the result is a barstem that out performs leading brands of aero road bars. An extra 3cm of flare has been added to the bars on the drops, a figure carefully calculated to meet the needs of both the OSTRO Gravel and OSTRO VAM.

The new Black Inc Thirty Four wheels are – like the OSTRO Gravel itself – dedicated to speed on gravel. Their 34mm depth maximises aero gains while keeping weight to a minimum and avoiding too tall a combined rim and tire side area, ensuring crosswind stability. They’re most aero with a 32mm tire for all-road use, yet also very effective for gravel tires up to 43mm. A hookless rim is designed to make it easy to mount tubeless tyres, in most cases with a regular floor pump. As with all Black Inc wheels, the hubs run on CeramicSpeed bearings for ultimate efficiency

Build My OSTRO Gravel

Key Features

At only 900g, the OSTRO Gravel is one of the lightest gravel frames available.

While the OSTRO Gravel pairs ideally with the Black Inc Aero Integrated Barstem, Factor designed the front end to be easily compatible with various third-party internal routing systems, so you can always have the exact touch points you want.

Leveraging Factor's in-house carbon expertise, we have precisely shaped the OSTRO Gravel’s tubes to create a tuned ride with optimised performance characteristics.

In line with rider demand and facilitating a reduction in aero drag and weight, the OSTRO Gravel is built exclusively for electronic shifting groupsets and disc brakes. Cable and hose routing is fully internal.

Fork offsets are based on the size of the frame to ensure optimum handling characteristics across all frame sizes so that every customer has the best ride experience.

Factor's engineers chose a round steerer which has been proven as the most durable solution for the rigors of serious gravel riding and racing. The 1-½” upper and lower bearings with a modified split ring allow for the cables to pass through the bearing, easing maintenance demands.

Mounting bosses added to the top tube and down tube so that you can make it feed stations or petrol stations, even on the toughest days.

The T47 standard for threaded bottom brackets ensures a secure fit and easy maintenance. It allows for the use of a wide range of crank spindle diameters and helps keep the bottom bracket shell robust for exceptional power transfer.

COLOUR OPTIONS

NAKED GRUNGE
WHITE GRUNGE

RECENT BUILDS

Get inspired and check out the latest builds to roll through our workshop

Buy Now

Secure your new Factor OSTRO Gravel with a £500 Deposit (Fully Refundable)

  • Factor OSTRO Gravel Frame, Fork & Seatpost
  • Black Inc Aero Integrated Barstem
  • CeramicSpeed BB & Headset
  • Computer Mount, Bartape, Mech Hanger + Accessories for Build
  • £5,200

SPECIFICATION & GEOMETRY

AStack
515

BReach
377

CFront Center
591

DWheelbase
999

EBB drop
76

FST angle
74.5°

GHT angle
71.2°

HTT (effective)
520

IST
450

JFork length
400

KFork Offset
56

LTrail
62

AStack
535

BReach
385

CFront Center
604

DWheelbase
1013

EBB drop
76

FST angle
74°

GHT angle
71.3°

HTT (effective)
538

IST
468

JFork length
400

KFork Offset
56

LTrail
62

AStack
555

BReach
394

CFront Center
605

DWheelbase
1014

EBB drop
74

FST angle
74°

GHT angle
72.2°

HTT (effective)
553

IST
483

JFork length
400

KFork Offset
50

LTrail
61

AStack
580

BReach
402

CFront Center
620

DWheelbase
1029

EBB drop
74

FST angle
73.5°

GHT angle
72.3°

HTT (effective)
574

IST
500

JFork length
400

KFork Offset
50

LTrail
61

AStack
605

BReach
412

CFront Center
638

DWheelbase
1047

EBB drop
74

FST angle
73.5°

GHT angle
72.3°

HTT (effective)
591

IST
523

JFork length
400

KFork Offset
50

LTrail
61

AStack
625

BReach
422

CFront Center
655

DWheelbase
1069

EBB drop
74

FST angle
73.5°

GHT angle
72.3°

HTT (effective)
607

IST
545

JFork length
400

KFork Offset
50

LTrail
61

Geometry

SIZE:
49
52
54
56
58
61
AStack
515
535
555
580
605
625
BReach
377
385
394
402
412
422
CFront Center
591
604
605
620
638
655
DWheelbase
999
1013
1014
1029
1047
1069
EBB drop
76
76
74
74
74
74
FST angle
74.5°
74°
74°
73.5°
73.5°
73.5°
GHT angle
71.2°
71.3°
72.2°
72.3°
72.3°
72.3°
HTT (effective)
520
538
553
574
591
607
IST
450
468
483
500
523
545
JFork length
400
400
400
400
400
400
KFork Offset
56
56
50
50
50
50
LTrail
62
62
61
61
61
61
VIEW SIZE GUIDE

FRAME
TeXtreme®, Toray®, Nippon Graphite® Pitch-Based Fibre
FORK
OSTRO Wide Stance Fork
SEATPOST
0 and 20mm setback available
BARSTEM
Black Inc Aero Integrated 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
BOTTOM BRACKET
CeramicSpeed T47A Aluminium cups / CeramicSpeed bearings with Wheels MFG 24mm BBRight Reducers / Adapters
MAX TIRE CLEARANCE
45mm
WHEEL SIZE
700c
BRAKE TYPE
Disc
FRONT AXLE
12 x 100mm thru-axle
REAR AXLE
12 x 142mm thru-axle
CABLE ROUTING
Internal
FINISH/COLOURS
Naked Grunge, White Grunge
MANUFACTURER WARRANTY
Limited Lifetime Warranty
FRAME
TeXtreme®, Toray®, Nippon Graphite® Pitch-Based Fibre
FORK
OSTRO Wide Stance Fork
SEATPOST
0 and 20mm setback available
BARSTEM
Black Inc Aero Integrated 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
BOTTOM BRACKET
CeramicSpeed T47A Aluminium cups / CeramicSpeed bearings with Wheels MFG 24mm BBRight Reducers / Adapters
MAX TIRE CLEARANCE
45mm
WHEEL SIZE
700c
BRAKE TYPE
Disc
FRONT AXLE
12 x 100mm thru-axle
REAR AXLE
12 x 142mm thru-axle
CABLE ROUTING
Internal
FINISH/COLOURS
Naked Grunge, White Grunge
MANUFACTURER WARRANTY
Limited Lifetime Warranty

START YOUR JOURNEY

Contact our team today and let's start talking about your dream bike