Factor Ostro Gravel Review: The Roadie's Gravel Bike

Factor Ostro Gravel Review

“Discover the All-Road All-Star. Speed is your goal. Every ride, whatever the surface, faster is what counts, and this is the gravel bike you’ve been waiting for. 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 tire capacity of 45mm, it’s ready to go anywhere, fast.” – Factor Bikes

Factor Ostro Review Video

Alternative Video Link for those reading via email subscription

In this video, JOM of the Gravel Cyclist crew provides his long-term review of the Factor Bikes Ostro Gravel. It’s carbon, it’s sleek, it’s fast, but is it comfortable in any way, shape or form?

Continued from Above:

Factor Ostro Written Review (or just watch the video!)

This bike is all about speed, no matter the road surface. In fact, a lot of this bike’s design comes directly from Factor’s Ostro VAM, but with larger tyre / tire clearance of 700c x 45mm.

Glancing at this bike, it’s pretty apparent Factor has been tinkering with this bike’s aerodynamic properties. Whether these carbon tube shapes combined with a wider gravel tyre, in this case a Panracer Gravelking SK in 700c x 43mm actually helps you to go faster, well, that’s a story for the wind tunnel.

Factor has left nothing to chance, everything is aero optimized. You have the Black Inc integrated aero bar stem, an aerodynamic seatpost that is home on a road bike, no cables to be found anywhere, and complimenting that, Black Inc’s excellent Thirty Four carbon gravel wheels with ceramic speed bearings. 34mm deep with 25mm internal width, and not a lot of spokes. Certainly, not the deepest wheelset, but a fine balance between too deep and just right. Ceramic speed bearings are fitting inside the hubs, and the headset bearing, very important considering the integrated cockpit. Bearings that favor long life, huge plus.

Factor has also adjusted sizing to be optimal for all tyre sizes. Remember, a wider tyre is also a taller tyre, which increases the “resulting” trail of a bike, whereas narrow tyres are less tall, the opposite is true. Factor has split the difference erring on side of slightly faster handling for wider tyres for gravel use, while keeping head tube angle in mind and fork rake. Long story short, you’ll be happy if performance riding is your thing, whether on tyres like these 700c x 43, or in Allroad mode with narrower 700c x 32’s.

Concerning the sizing, you must do your homework with this bike. Factor’s sizing chart differs from most you may be used to, because top tube length is not mentioned, nor is head tube length. You’ll need to know your reach number. That methodology of fitting isn’t for me, and I’m not alone. I relied on the assistance of a good mate at Factor USA HQ, G’Day sully if you’re reading! Sully measured the top tube and head tube lengths, which then allowed me to calculate the appropriate stem length. As this front is completely integrated, it’s not like you can easily swap a stem. Incidentally, the review bike is a size 52, but that does not refer to the top tube length. Confusing.

The groupset on this Focus Ostro Gravel is the formerly top tier SRAM Red eTap XPLR AXS 12 speed, which was recently superseded by the company’s 13 speed variant. The 12 speed version of this drivetrain is excellent, and still very relevant. On this sample bike, you’ve got a 1x drivetrain with 40T chainring, and an 10-44 cassette. Nothing has changed, I still prefer 2x and the Ostro Gravel caters to that with an available front derailleur mount. In the absence of this mount, you can swap to a smaller cassette for flatter terrain, like the 10-36T cassette from SRAM I have been running this bike with. You can see my review of this fabulous SRAM Red eTap XPLR AXS 12 speed linked here. Incidentally, I have the 13 speed variant of this drivetrain for review, stay tuned!

Wrapping up, there are Ceramic Speed bearings inside the Ostro Gravel’s threaded T47 bottom bracket, and believe it or not, there are some mounting points on this bike despite its penchant for speed. You get the usual bottle cage mounting points on the downtube and seattube as you would expect. Adding to that, the excellent top tube mounting point for a bento box, feed bag, etc. Below the down tube, getting close to the bottom bracket, a mounting point I like to call the cow $hit catcher position, for obvious reasons… draw your own conclusions.

The Riding Experience of the Factor Ostro Gravel Ride

The Factor Ostro Gravel isn’t the first gravel bike optimized for aero. That claim belongs to the 3T Exploro, a bike I reviewed a long time ago and loved, until about 100 miles into the ride, when I really felt the fatigue of its overly stiff frame. The Ostro is similar in this regard. it looks the business and is perfect if you’re a fast roadie coming across to gravel. But, the trade-offs are substantial.

Dialing your tyre pressure is critical and wider tyres are recommended. The ride quality is stiff and harsh at times. Factor doesn’t make any excuses for this, it’s abundantly clear in their marketing, but the fatigue will add up as the miles / kms add up. Despite the rough riding nature of this bike, I absolutely love the fit, the feel, and how the Ostro handles in and out of the saddle, on the drops, it doesn’t matter. It isn’t a bike I would favor for overly dodgy, rocky terrain for obvious reasons. The journalist bollocks parade who overuses the “compliance” word, well, that ain’t happening on the rear end of this bike. However, for some of the big name races we see nowadays with smoother roads, this bike would be a solid choice. But 200 miles on it, yikes.

Handling is superb, if you didn’t get that impression from me already. it isn’t twitchy and nervous, just right for barreling through a corner, or picking a line through a dodgy patch of gnarly gravel, even though you will feel it. I’ve always preferred wider is better tyres before the mainstream media and some pro riders made this discovery. Wider tyres only benefit this bike.

The cockpit, mostly I like it. Somehow I got my fit just perfect, I really like the handlebars, including their tiny amount of flare. My solitary complaint is the flat bar tops don’t agree with my hands after many hours. Handlebar choice is a personal concern, whereas your hands may be right at home here. The seatpost binding mechanism works well, with a single bolt accessed atop the seattube, beneath the downtube. Thankfully, the seatpost hasn’t budged.

I cannot vouch for how the ostro gravel rides with 32mm tyres. I’m sure its fast, and this bike could be a good one-bike stable type machine, provided you’re aware of its shortcomings. I believe there is some decent value with this bike, even if this spec will set you back $US 9,000. You have top tier parts from SRAM and Black Inc, and a power meter. The big miss on the bike nowadays is the limitation of 700c x 45mm tyres, 700c x 50mm is rapidly becoming the norm (about farrrking time!). Lower spec builds of this bike are available starting at $7,500 with Force XPLR AXS. When you consider the frame module is $US 5500, it gets difficult to justify the price, and perhaps purchase a pre-built option from Factor.

In summary, this bike is expensive, its rough performance ride isn’t for everyone. but if you can get past those factors, pardon the pun, this bike is amazing. The Factor Ostro Gravel is all about speed, performance and not a lot of versatility, but… it could be right for you.