Factor’s original Ostro Gravel was quite pioneering, insofar as it was one of the first aero gravel bikes on the scene, along with the 3T Exploro, before aero gravel bikes were really a thing. Gravel racing has come on a long way since 2023, and while the Ostro Gravel still is a competitive machine, it’s starting to seem a little long in the tooth.
In the lead-up to Unbound, much like the flurry of new bikes that arrive before the Tour de France, we get some new gravelly machines to pore over before their actual releases. Factor has posted a couple of videos on its official Instagram page following the Santa Vall gravel race that show Romain Bardet and Norwegian gravel champion, Magnus Bak Klaris, aboard what appears to be an overhauled Ostro Gravel model. Whether it’s ‘hiding in plain sight’ or ‘deliberate leak to generate media interest’, we will leave up to you, but whatever the tactic, the end result is the same.
Bigger forks, bigger tyres
The old Ostro Gravel, or OG as the old one became known colloquially, had wheels aero optimised and marketed around a 32mm tyre (at the time of writing), though it shipped with a 43mm, and has a max clearance of 45mm. This, given current trends towards massive, MTB-size tyres in gravel, is just a little too narrow.
I saw pro riders cramming more into their frames at The Traka last year, but the old OG isn’t going to challenge the likes of the new Specialized Diverge, or the Lauf Seigla in the tyre department. Personally, I also found the old OG quite uncomfortable. The frame is extremely stiff, and wider tyres would have been of great benefit.
The new version looks to have a far wider fork, and both Bardet and Klaris look to be using a tyre around 50mm wide. From the side, it looks like there would be plenty of room for more rubber, but a more front-on view of Bardet’s machine reveals sloping shoulders that likely form the pinch point for the front end.
Rear-end clearance is often the harder thing to achieve, and the new version looks to have dropped the chainstays to add more room. Even so, the rear tyre is perilously close to the seatpost at the size they are running, so even if front-end clearance goes up larger, it seems unlikely that it will at the rear end.
The fork legs themselves, as well as being wider set, are also deeper in profile, with a flatter top tube and perhaps a slightly deeper downtube to add to the aero package. The head tube is clearly different, with a very pronounced hourglass figure to it, which is a hallmark of modern aero machines.
While we can’t be sure from the images, it seems likely that the bike will be a 1x-only machine. Factor’s new do-it-all Aluto remains 2x compatible, but front derailleurs impact tyre clearance quite severely, as well as being less aero, so we wouldn’t be surprised to see Factor ditching the inner ring completely here.
Bigger wheels
The old OG shipped with 34mm deep all-rounder wheels, the same that the Aluto comes with, but both Bardet and Klaris are riding on much deeper, seemingly unbadged wheels. It is likely, given that gravel is getting more aero by the month, that these will be the production wheels that come with the machine, which does represent a pretty drastic shift as they’re butting up against the UCI’s maximum depth for road wheels (no such issue on gravel, it must be said). But they could also be something unbadged upon which to test the frameset. They’re also running different cockpits to each other, but I suspect it’s due to fit reasons, and it seems unlikely that the new OG will ship with anything other than an integrated front end.
As for further details, well, we will have to see what comes out in the wash. Cyclingnews has reached out to Factor for comment.



