Factor Ostro VAM: The exclusive first-ride review

Factor, a manufacturer focussed on producing performance carbon bikes, calls it the road bike quiver-killer. A disc-equipped aero bike that can be built to the UCI weight limit but that’s comfortable enough to race at Paris-Roubaix. Or put another way, most road bikes are traditionally grouped into three segments. You…

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Factor, a manufacturer focussed on producing performance carbon bikes, calls it the road bike quiver-killer. A disc-equipped aero bike that can be built to the UCI weight limit but that’s comfortable enough to race at Paris-Roubaix.

Or put another way, most road bikes are traditionally grouped into three segments. You have the lightweight climbing bike, the aero bike and then the comfortable endurance bike. Factor has the lightweight climbing bike, the Factor 02 VAM. Meanwhile, The One remains the manufacturer’s dedicated aero bike. And then comes the new Ostro VAM, a “mid-depth aero bike” that’s somewhat trying to steal the lunch of all three road bike segments.

Such a do-it-all bike isn’t a brand new concept, and bikes like the Pinarello F12 and Scott Foil (which has won Roubaix …) share a similar approach and the newer generation of lightweight-turned-aero bikes all edge toward what the Ostro VAM aims to achieve. Then there’s the new Cervelo Caledonia 5 which has a number of similarities, too.

But depending on how you slice it, the Ostro VAM is still somewhat of a unique beast.


The Ostro VAM – a bike that gets its name from the winds that sweep through the Côte d’Azur and Nice – has already been spotted in use at this year’s Tour de France. And now it’s official. Factor managed to get a pre-production sample into my hands late last week and I quickly put some local laps on it. Here I take an in-depth look at what this new bike is and how it rides.

Aero with a balance

[ct_story_highlights]What: An all-round aero bike designed to be raced at Paris-Roubaix. ||Key features: Room for 32 mm+ tyres, concealed cabling, mid-depth aero design with sharp edge truncated profiles, low frame weight. ||Weight: 875 g frame weight (54 cm painted, pre-production), 420 g fork, 305 g handlebar/stem. 6.88 kg as tested (without pedals).||Price: US$5,499 / £5,400 for a frameset (includes one-piece handlebar/stem, seat post, CeramicSpeed bottom bracket, CeramicSpeed headset). Complete bike options from US$8,199 / £7,850.||Highs: Well-rounded ride, generous tyre clearance, impressive weight, not rattly, threaded bottom bracket, impressive tube shapes and construction, carbon fork steerer safety protection, graphic design.
||Lows: Pre-production test sample suffered torsional frame flex, care required with brake hose routing at front end, one-piece handlebar is repurposed. [/ct_story_highlights]

The Ostro VAM is the company’s first ground-up project overseen by Factor’s new head of engineering, Graham Shrive. Previously the head of engineering at Cervelo, Shrive certainly has plenty of pedigree in designing bikes that are commonly considered the benchmark in aero performance.

As a result of Shrive joining Factor, the Ostro VAM is a fresh design that shares little in common with Factor’s existing (and continuing) aero bike, The One. The One’s Twin-Vane is a unique twin-down tube that aims to create an incredibly stiff frame without giving up on aerodynamics. In an effort to shave weight, the Ostro employs a more traditional down tube, one which uses a truncated NACA airfoil shape.

According to Shrive, the new Ostro VAM is a bike that aims to be extremely aero without compromising on frame weight, handling or comfort. In turn, there are some concessions made in the tube profiles to find such a balance and so the Ostro doesn’t push the UCI’s boundaries of what is allowed in tube shapes. Or put in a numerical way: the 02 VAM is built around a 40 mm depth down tube, The One measures in at approximately 80 mm, and the Ostro splits the difference.

Now that’s not to say the Ostro is traditional. The front fork takes the approach of giving an extremely wide berth around the front wheel and is aerodynamically optimised for a racing-width tyre (26.4 mm to be exact, not-so-coincidentally what the Israel Start-Up Nation cycling team uses). It’s an extremely similar approach to British Cycling’s new Lotus-designed track bike.

That thickly shaped fork then flows onto an easily overlooked channel on the underside of the down tube (just behind the head tube), something Factor calls the Reversing Flow Energising Channel. Catchy, huh?

The Reversing Flow Energising Channel.

Basically the area behind the fork crown is known to be fairly turbulent with stagnant air coming off the forward-rotating front wheel. Many aero bikes overcome this by closely shrouding the wheel with the frame. Shrive’s approach is to create a converging nozzle in this space to help accelerate the air down the frame. Or more simply, it aims to use the air coming past the head tube and fork legs and have it take that no-good stagnant air away without making a scene.

Coincidentally, that generously wide and slightly bow-legged fork allows space for a 32 mm tyre on a 21 mm internal width rim. That allowance is to ISO spec and so realistically there’s room for actual 34 mm tyres to be fitted front and rear.

Of course there are other aero optimisations wherever you look. The horizontal top tube with its concave surface is one. The concave surface along the inner side of the down tube is another. There’s the dropped seatstays that meet the cut-out seat tube. The deeply shaped bottom bracket and head tube junctions make good (and UCI-legal) use of the wider dimensions needed in those areas.

One aero detail that’s harder to see is that Factor claims to build the Ostro with tighter corner radii at the truncated edges than much of its competition. According to Shrive this makes the cut-off airfoils more efficient but commonly isn’t done due to manufacturing difficulty. Accordingly, most contract manufacturers won’t go less than a three-millimetre radius, whereas Factor, which manufacturers its own frames, is willing to push that figure to just one millimetre.

Difficult to capture, but the Osmo VAM’s frame shapes feature sharper radius edges than most.

Of course there are reasons why most manufacturers won’t produce such sharp edges out of a composite material, and most of it comes down to the ability to consistently and repeatedly produce good (and safe) results. The harder something is to manufacture, the more it costs to do right. If you believe Factor’s word, then the fact they’re the manufacturer, and one that mostly specialises in framesets and not complete bikes, allows them to more easily absorb those costs.

One other element helping achieve all these extreme shapes (and a low weight) is the use of some fancy materials. That’s where the VAM naming comes in, and is in reference to the frame being made from top-end no-expense-spared materials. Namely, Factor employs TeXtreme’s spread-tow material at the base layer, which according to Shrive, is an approach that’s unique to Factor. Factor uses this patented material to provide a barrier between the latex moulds and the carbon layup to help produce a better-controlled and more consistent outcome. And like the 02 VAM, the Ostro also uses Boron fibres at the seat tube to help reinforce the internal wedge clamp.

All of this sounds great, but how fast is it? Well, the answer to that will need to wait until this global pandemic eases. Due to travel restrictions Factor is yet to get the new Ostro in a wind tunnel. Still, Shrive seems confident, at least based on CFD simulations, that it will prove competitively fast with many well-liked aero bikes. And hey, experience in making proven fast bikes has to be worth something, right? I guess time will tell.

A light load on the scales

Factor’s The One is quite an impressive machine to look at (and sprint on, speaking from experience), but that Twin Vane down tube adds great complexity and makes it a little portly. Figures I’ve seen suggest the most recent generation of The One has a frame sitting at around 1,150 g. By contrast, the Ostro’s 875 g figure for a painted 54 cm frame is quite impressive.

Other components used are equally easy on the scales, such as the 168 g seat post (available in a 15 mm set-back or zero offset), or the supplied 305 g one-piece handlebar and stem. The 420 g fork is less impressive, but a look at its unique crown, deep cross-section legs and replaceable thread makes the figure more inspiring. All told, my test sample bike weighs just 6.88 kg (without pedals). Yes, that’s with relatively shallow wheels, but still, this thing isn’t heavy.

Even the seat posts are competitively light.

Such weight loss means the Ostro VAM offers less torsional stiffness than the notoriously stiff The One. According to Shrive, the figures are closely comparable to the regular 02, and a little stiffer than the 02 VAM that I previously found to be wonderfully efficient under power. I actually dispute Factor’s claim here, but I’ll come back to this.

Vertical flex, aka compliance, is something that Shrive apparently played close attention to. Notably, the seat post isn’t anywhere near as deep in its profile as the UCI allows, while the pencil-thin seat stays are noticeably dropped on the seat tube (Factor names them “Vista-style seat stays”). Up front, there’s a detectable amount of flex from the handlebar setup.

Slender stays and oodles of tyre clearance.

That comfort is of course by design. As Shrive explained to me, he’s previously worked with athletes that wanted to ride full-blown aero bikes at Paris-Roubaix and he always thought those bikes weren’t ideally suited to the task. And so the Ostro was built to be comfortable and efficient over cobbles.

Speaking of comfort, the Ostro shares identical stack and reach figures with Factor’s 02 VAM and The One. The goal is that its pro riders can mix and match between the models without a major change to fit.

The geometry itself closely mimics the 02 VAM, with fairly traditional race angles matched with an approximate 57 mm trail figure when set up with 26 mm tyres. The trail figure remains fairly consistent across the sizes (it actually slows slightly as the sizes progress), something that’s made possible by using three different fork offsets across the size range. Fitting wider tyres will naturally slow the trail figure further, exactly what you want when you most need more voluminous rubber.

The progressive trail figure isn’t commonly seen. Shrive’s reasoning is that smaller riders have a lower centre of gravity and so a faster handling bike is more easily controlled. Chainstays are 405 mm in length for all sizes, except for the 58 cm frame which has 408 mm stays.

Factor will only offer the Ostro VAM in a choice of five frame sizes. Notably, tall riders requiring a 61 cm frame are currently out of luck.

The techy bits

Ok, time to dive into the finer technical elements that can so easily make or break a bike (literally and figuratively).

I’ll reiterate that my sample is pre-production and that it’s entirely possible the finer details will change. For example, Factor has already told me that the BBRight-esq press-fit bottom bracket is being replaced with a T47 Asymmetric threaded bottom bracket.

The production version will feature a T47 bottom bracket amongst that field of carbon.

This T47 Asymmetric is effectively a threaded version of an offset bottom bracket system like BBRight. Basically, it’s an adapted version of T47 that won’t be unique to Factor — they didn’t create it, it’s an open “standard” (let’s call it a fitment) and it’ll work just fine with existing cranks. Factor’s website offers more details about this.

What I do know is that Factor will supply a suitable CeramicSpeed bottom bracket with both its framesets and complete bikes. And while this is Factor’s first bike to feature a T47 bottom bracket, it likely won’t be the last.

Factor’s owner, Rob Gitelis, clearly stated that this last-minute change was purely consumer- and media-driven (sorry, not sorry) and not because there’s any issue with press-fit systems when manufactured correctly. Gitelis pointed out that this update will add approximately 30 g to the frame, but the 875 g frame figure should hold true given my sample had two practise coats of paint on it while they figured out the final graphic design). Still, I consider this late addition to be grams well spent.

The integrated wedge at the seatpost has been made larger compared to Factor’s previous bikes in order to increase the surface area (holding power). And I can confirm that the 4 mm bolt is easily accessible with common tools. My only worry is that the supplied seatpost has extremely thin walls, so certainly follow torque guidelines on this one.

At the front of the bike there’s a whole number of clever details hidden from the outside. Factor recently updated its relativelynew 02 VAM with a D-shaped fork that allows fully concealed cable routing down the front face of the fork steerer. The Ostro VAM uses the exact same system.

Factor provides a matching one-piece carbon handlebar and stem assembly from its sister brand Black Inc, something that weighs just 305 g (making it one of the lighter options available). Better yet, the design is accepting of other internally routed stems and handlebars, too, and setups from Deda, FSA or pretty much anything that lets cables be run into the back of a stem, will work.

Additionally, Factor is currently working on a headset top cap that’ll allow cabling to enter below the stem, instead of being run through it. And yep, the headset spacers split, so you can raise or lower the stem height without having to disconnect brake hoses. Of course, the usual limitations and hassles of such a setup remain, namely that the brake hoses are routed through the top headset bearing (which is a commonly available 1 1/8″ item).

These aluminium steerer items are designed to give the Ostro a little extra safety.

Factor has done some clever things in order to achieve this clean setup, namely there’s a unique expanding wedge to fit the D-shaped steerer, and it offers plenty of depth and support to the steerer.

That expanding wedge interfaces with a pronged aluminium plate that runs from the top of the steerer and down past the compression ring of the headset. Not only does this recreate a round steerer for the stem to clamp to, it also offers the carbon some welcome protection.

The pronged piece is slid down the front of the steerer, while the expansion wedge locks it into place.

According to Shrive, this design means the headset compression ring can’t cut into the carbon steerer in the event of an unexpected force to the front wheel (typically a crash). Or in other words, you won’t reenact George Hincapie’s painful exit from the 2006 Paris-Roubaix. All told there are some comforting aluminium fail-safes built around that extremely slim D-shaped carbon steerer (as long as you don’t exceed the maximum allowed exposed steerer limit!).

However, there is one limitation of the design. The Ostro VAM works with electronic drivetrains only.

First rides review

Ok, so how does the Ostro VAM ride? Well, quite similar to how Factor describes, it’s an aero bike that doesn’t feel like an aero bike.

Now keep in mind that my time on the Ostro VAM was fairly limited, and the bike I’m riding is pre-production. Still, being able to ride a bike on local roads in my own controlled setting is far more telling than attending any launch.

Light bikes climb well, and that’s certainly true for the smooth-riding Ostro.

What’s most obvious from the get-go is the bike’s low weight, especially that lack of mass at the top half of the bike. This makes it an immediate pleasure to whip back and forth, and I found it a rewarding experience with sudden changes in pace.

Of course part of this feathery feeling was the result of the lightweight Black Inc Thirty wheels. These shallow wheels are arguably the wrong match for this aero-fied bike, but as covered in the sidebar below, Factor’s all-new matching Forty-Five wheels weren’t ready to review.

The Ostro’s ride quality is balanced front to rear, with the flex in the bar taking the sting away from poorly surfaced roads, while out back those dropped chainstays do indeed seem to help take the edge off.

It’s worth mentioning that the Ostro’s seatpost is noticeably firmer than the skinny D-shaped posts used on bikes like the Specialized Tarmac, BMC TeamMachine and more. Of course, the Ostro is still a race bike and you’ll feel what your wheels are hitting, but equally, it did a great job of numbing dead roads and taking the uncomfortable jolt out of more visible imperfections in the road.

What’s interesting is that Factor claims the Ostro VAM is stiffer than the 02 VAM, and while it’s been at least nine months since I last rode that lightweight climbing bike, I actually think my pre-production sample of the Ostro is softer, and I mean that in both a torsional and vertical sense.

My pre-production Ostro VAM felt softer than expected through the front end.

The Ostro is certainly plenty stiff through that absolutely massive bottom bracket junction and that wide-stance fork, but I could detect a little flex between the seat tube and the head tube. This didn’t seem to impact how the bike cornered, but rather all-out sprints didn’t feel quite as satisfying as a really stiff bike does (such as Factor’s The One, for example).

Having said that, I passed this feedback onto the team at Factor and was told that they’d received similar feedback from the Israel Start-Up Nation team. As a result, the production version of the Ostro will be stiffer than the sample I tested. Additionally, the larger 56 and 58 cm sizes will be proportionally stiffer again. It will be interesting to see whether the production bike gains much weight as a result.

Meanwhile, I recall the 02 VAM suffering from a little nervousness on washboard tarmac, the likely outcome of it being a little too stiff in the vertical plane. By contrast on the same surface, the Ostro felt more controlled (tyre model is different, but width and tested pressures are the same). Again, a nine-month gap means I can’t be absolutely certain of this, but I’m still confident enough to write it. However, it’s entirely possible that the stiffening of the production bike will impact the compliance, but for now I have no way to confirm this.

The handling is certainly familiar, and that’s no surprise given the angles are quite like the 02 VAM’s. This is a sporty bike that changes direction with minimal input just like a good race bike should. And given the rather traditional, popular and well-proven numbers used, that shouldn’t be surprising.

One element to keep in mind is that the Ostro VAM is clearly optimised in aerodynamics and handling around a racing-width tyre (26-27 mm measured width tyre), and as such, features a 70 mm bottom bracket. That’s a fairly regular figure for a performance road bike, but it’s worth noting that the Ostro will become relatively tall if you max out the tyre clearance. This criticism isn’t at all unique to Factor and bikes designed to handle a wide array of tyre sizes will always have a compromise.

Of course, the reach figures remain on the slightly lower side of things, and so that’s certainly something to pay close attention to if you require a more upright riding position. Factor provides a taller headset top cap to be used along with the optional stem spacers, but those will only go so far.

I get on well with Black Inc’s handlebar shape.

The touchpoints on the bike left me little to complain about. The Black Inc handlebar offers a drop shape that keeps my wrists happy, while the tops are comfortable to hold without being cumbersome. Black Inc provides its own integrated aluminium computer mount with the bike (just Garmin and Wahoo pucks for now) — no complaints here.

However, given I’m paid to nitpick, I will. The handlebar used is actually just a slightly modified version of Black Inc’s previous bar, and so it still features grooves for external cabling on its underside. Personally I’d like to see a more dedicated bar (for internal-only routing) offered, and I suspect a few further grams can be shaved by doing this. On the plus side, those spare cable grooves gave my fingers something to dig into.

Speaking of the bars, my pre-production sample made a popping sound when you turned them past 45º. A little inspection proved that the noise was the rear brake hose catching the edge of the steerer on its way past the front brake hose and into the frame. Some careful assembly, and perhaps being a little more generous with the foam insulation tubing should keep this one quiet. And to be fair, it’s not something I heard while riding the thing.

Ok, time to talk about value for money. I typically shy away from this topic — just because I can’t afford something doesn’t mean it’s not good value. Likewise, don’t tell me my $100 hex keys are bad value.

Anyway, I digress. Factor effectively sells factory-direct in most regions which allows the brand to be price-competitive despite their relatively small market size. The Ostro VAM frameset, which includes the frame, fork, seatpost, integrated bar and stem, CeramicSpeed bottom bracket and CeramicSpeed headset, will retail for US$5,499 / £5,400 (inc VAT).

A complete bike with Black Inc’s new Forty-Five wheels and a SRAM Force AXS groupset will retail for US$8,199 / £7,850 (inc VAT). A bike like this one, with SRAM Red AXS will retail for US$10,099 / £9,250 (inc VAT). Shimano Di2-equipped models will also be available in select markets. Now those aren’t small pricetags, but they at least look pretty good when put alongside the likes of Trek, Specialized and a bunch of traditional Euro brands.

Those graphics.

Finally, I’ll sing praise for the attractive “Flicker” graphic design as tested. The detailed line graphics are laid over the top of a minimalist clear coat that shows Factor’s handiwork beneath. It’s a design that received endless praise and sniffs from passers-by and their dogs while filming. It’s not often I have non-cycling strangers wanting to stop and look closely at a bike.

Factor will also offer the Ostro VAM in graphic options called Soho Mix and Sicilian Peach. I’m pretty sure I’ve had Sicilian peach in a G&T before; it was nice. Images of these designs are in the gallery below.

The modern all-rounder

Factor’s new Ostro VAM is unquestionably a modern all-rounder. With its generous tyre clearance, unmistakable aero design, and a respectable weight, it really does serve as the well-mannered aero road bike that most speed enthusiasts should be on.

However, while the Ostro VAM is an extremely modern bike, I don’t believe it’s entirely unique. 2020 has seen many of the biggest brands give their lightweight climbing bikes the aero overhaul, and in many ways, the Ostro most closely competes with these. While wind tunnel data isn’t yet available, at a guess I’d expect the Ostro to best many of its lighter-weight rivals once at speed. Meanwhile, some of those rivals have the edge on the scales and perhaps in all-out frame stiffness, too.

On the other side, a number of brands have taken the path of stripping the weight away from their aero machines. And again, the Ostro finds competition here, although it’s likely to be lighter and better-mannered in crosswinds.

And then there’s another comparison – the as-modern-as-it-gets Cervelo Caledonia 5. The Caledonia 5 offers more features for the everyday rider, such as fender compatibility and taller stack setup, while the Ostro VAM takes a more performance-driven path with quicker handling, a (subtly) more aggressive stack, and a slightly lower system weight.

This bike is certainly well-rounded. I almost always prefer riding lightweight (all-rounder) bikes compared to dedicated aero steeds, and while the Ostro is well into the aero realm, I actually got on quite well with it.

In my opinion, a bike like the Ostro VAM is the future of performance road bikes and is where the industry is headed. A do-it-all, jack-of-all-trades race machine that’s 95% as good at specific tasks as more specialist machines. Perhaps the bigger question is what the Ostro means for Factor’s other bikes. I really can’t see them selling too many The Ones with this thing about.


Sidebar: New Black Inc Forty-Five wheels

Factor’s sister company, Black Inc, has a new mid-depth wheelset on the way that’s designed to suit the Ostro. Named the Forty Five, these 45 mm-depth wheels are intended to replace the existing Fifty wheel.

The Forty Five wheels are disc-only and tubeless-ready with an internal rim width of 20.7 mm (external width figure not provided). They feature a NACA 0018 airfoil shape with an exterior shape optimised for 25-28 mm tyres. It’s a shape that Shrive claims is extremely efficient up to common yaw angles of 10º and offers a stable ride.

The wheels spin on Black Inc’s own hubs which feature Ceramicspeed bearings and a new ratchet system at the freehub (DT Swiss’ patent on the original Star Ratchet system has expired…) These wheels should weigh approximately 1,400 g and will retail for US$2,349.




[ct_gallery_start id=’ct_gallery1’]

The Ostro VAM in the “Sicilian Peach” paintwork.
The Ostro VAM with those “Soho Mix” vibes.


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