Factor has followed up their latest superlight climbers’ and split downtube sprinters’ race bikes with the all-new Ostro – blending both light weight & aerodynamics in a single all-rounder aero road bike. Claiming to be deliver on fast aero performance and comfort even over rough roads without any weight penalty, Factor calls the Ostro a “quiver killer”, making it the ideal stage race bike for their Israel Start-Up Nation pros who are racing the new bike now at the 2020 Tour de France.
2021 Factor Ostro VAM lightweight, aero road race bike
A couple of weeks ago our weight weenie tendencies were fawning over the latest version of Factor’s lightweight 677g O2 VAM race bike & sub-1kg Black Inc carbon tubulars, but even then we heard chatter of a new bike blending O2’s light weight with One’s aero speed. Now that bike is here – the Factor Ostro – and it brings with it another new set of light carbon wheels – the new Black Inc Forty Fives.
Combining the best of Factor’s signature lightweight carbon construction and a simplified form of their aerodynamic focus, the new Ostro aims to be the only bike you’ll need to race from the cobbled Classics to a mountainous stage race.
In fact, Factor’s engineering director said the bike was a direct response to working with pro team riders, “especially at Paris-Roubaix”. Graham Shrive explains that “every year there would be a couple of riders who wanted to use their aero bikes to get that advantage, no matter how poorly suited they were to the cobbles. Plus, of course, pros have always wanted an aero bike with no weight penalty, or a super light bike with no drag penalty in the valleys, as the climbers might see it. Instead of battling to get them on a bike made for the cobbles, we decided to build them what they wanted, and it turns out to be a hell of a bike.”
Factor Ostro – Aero Road Tech Details
The Ostro also becomes the latest to get Factor’s top, extra-light VAM moniker, bringing with it a suitably light 780g frame weight claim (54cm with Flicker paint scheme). The disc brake-only Ostro also takes on the latest trend of fully internal cable routing (within a standard 1.125″ upper headset bearing!) and is only compatible with top-spec electronic drivetrains.
Aero dynamic advantage comes from ‘mid-chord’ aero profiles used across the frame, with truncated NACA shapes that keep the same cross-section area into the wind as the O2 VAM, reducing drag with minimal weight penalty and maximizing stiffness at the same time. The Ostro also gets wide set fork legs for more free-flowing air space around the pro team’s standard 26mm tubulars. That space also means there’s room for up to 32mm tires max, for when the roads get rougher or you are just looking for increased comfort. Then, tiny dropped seatstays out back work with bigger tires to filter out bumps for a smoother ride.
While it doesn’t use their One split downtube idea, the upper part of the Ostro’s downtube narrows & transitions into a specially shaped “Reversing Flow Energising Channel” in the fork crown to reduce drag from air coming off the spinning front wheel. “Incoming airflow to the fork is focused through a converging nozzle to accelerate the reversed flow out of this area, significantly reducing the pressure changes in this area, improving laminar flow and cutting drag.”
The Ostro features a T47 threaded bottom bracket, flat mount brakes, 12mm thru-axles, three different size-specific fork offsets, an internal wedge-style seatpost clamp, a proprietary aero seatpost with 0 or 25mm setback, and it can be built up either with sister brand Black Inc’s one-piece bar/stem or a conventional cockpit with cabling entering the steerer below the stem.
The race-ready, race-proven geometry of the Ostro is identical to the O2, making no compromises in handling to fit its bigger tires. That also was especially important for the pro team riders, so they could seamlessly switch back and forth between their race bikes.
Black Inc Forty Five aero carbon wheels
Together with the Factor Ostro, Black Inc also has a new mid-depth Forty Five aero wheelset to launch. Designed to balance aerodynamics & light weight, the disc-only carbon wheels are 45mm deep & tubeless-ready with a 20.7mm inner width and NACA 0018 shape. The $2350, 1492g wheels are available separately or with complete Ostro builds and spin on CeramicSpeed bearings – with first deliveries in November 2020.
Factor Ostro – Pricing & availability
The new Ostro is available now for pre-order direct from Factor in three standard paint schemes – Flicker, Soho Mix & Sicilian Peach.
Get it as a framekit for $5500 including the aero carbon frame, fork, seatpost, integrated Black Inc barstem, a CeramicSpeed BB & headset.
Complete bikes are available in two SRAM AXS builds, both including the new Black Inc wheels: for $8200 with Force AXS or $10,100 with Red AXS.