'In every ride situation, it’s sensational' - the Factor OSTRO VAM

Beyond its aero and lightness, the OSTRO is packed with bleeding-edge features

This article was made in association with Factor.

The enemy of my enemy is my friend. For years, aerodynamics and lightness have quarrelled over which should be the dominant quality in a race bike, their priorities seemingly mutually exclusive. The most aero frame shapes are not light; the lightest are not aero. We would have to pick a side, choose our weapon, forge a temporary alliance based on whether we were going into battle with the wind or the mountains.

Factor brokered peace with a simple truth. Aerodynamics and lightness share a common foe – the clock. Beating it requires a combined effort. No more compromises. The OSTRO VAM was to be the vehicle by which this new gospel was spread, the bike that all of the pros would want to ride in all of the races, from climber to sprinter to rouleur, and therefore the ultimate machine for cyclists wanting one bike for their racing, training and holidays in the mountains.

Of course, nearly every bike brand has embarked upon this quest for superiority, to be the one that holds the advantage, the magic victory multiplier. Millions have been spent to raise the bar to its current lofty height; Factor knew that to push it further still would require a different approach. Fortunately, that’s what they’re all about.

At this point, a brief history is required. Stick with us, as it’s a better story than most. Factor Bikes began as a side project of a British motorsport engineering company, Beru F1 Systems. The initial concept bike, the Factor 001, was made to demonstrate the skills of a firm that wasn’t feeling sufficiently challenged making state-of-the-art steering wheels and wiring looms for most of the Formula One grid. It drew so much admiration that they felt compelled to put it into production. The subsequent Vis Vires was radical, exciting, fast...and so complicated to make that they struggled to find a manufacturing partner willing and able to take it on.

Rob Gitelis was the man who stepped forward, a hugely respected industry figure with decades of experience making bikes for some of the world’s biggest brands. Parallel to the emergence of Factor in the UK, Gitelis had been growing disillusioned with the industry’s focus on cost saving over engineering. When the opportunity came up to buy Factor, he took it and soon recruited the talented and wildly enthusiastic Graham Shrive, formerly of Cervélo, as head of engineering.

Factor Bikes suddenly found itself in a unique position. Here was a young brand with F1 in its DNA, engineering at its core, an expert team, and its own factory.  Virtually every other brand contracts its manufacturing to a third-party factory, which naturally takes a margin and won’t feel as invested in the quality of the product. Factor controls the entire process – it’s the brand’s superpower.

On top of that, Factor sells direct to you, cutting out distributors and shops in a now familiar business model made famous by the likes of Canyon. Instead of dropping prices, Factor says it invests in materials and processes, using its own factory to iterate, innovate and generally do things the hard way if it means an increase in ride quality.

It was armed with all of these advantages that Factor set out to develop the OSTRO. “The first thing we did was set a weight budget of 780g and then the goal to be the most aero frame at that weight,” says Gitelis. That weight figure raised some eyebrows. “I said it would cost a fortune,” says Graham Shrive, “and Rob just laughed.” It was time to shake things up and deploy that superpower.

Truncated airfoil shapes are the foundation of the OSTRO’s speed. This is standard across the industry, but the devil is in the detail. A longer airfoil is faster but heavier, and the OSTRO had to be light. “It was about looking for a sweet spot of aero performance versus weight as the airfoil shape becomes more truncated,” says Shrive. “That’s where the magic was.”

With the most efficient shape identified, the next step was to get the most out of it. After length, the next critical element to performance is the acuteness of the corner at the truncation – the sharper the better. Here is where owning their factory allowed Factor to go further, make life hard for themselves, and reap the rewards, as Shrive explains: “The radius on the truncation of the downtube was very challenging. Most factories wouldn’t have let us do that. Usually, they’d do a 5mm radius and we used 3mm. It made a big difference to the complexity and also the performance.”

There are plenty of other visible aero features – one-piece cockpit, aero post, dropped seatstays – that are familiar concepts. On the other hand, the most original aero feature is all but invisible. Tucked into the top of the downtube and integrated to the fork crown is the Reversing Flow Energising Channel, which accelerates a jet of airflow into the space between the fork and downtube, blasting away stagnant airflow caused by the forward-rotating front wheel and tyre. In turn, this allows for cleaner airflow onto the downtube, which is essential for aero performance. “The flow channelwas the most challenging feature to engineer while preserving steering movement and without adding a tonne of weight,” says Shrive.  

The Wide Stance fork has dual benefits: it offers clearance for a 32mm tyre,  delivering on the OSTRO’s mission to be an aero bike for Paris-Roubaix; and it allows optimal ‘through flow’ when used with a 26mm tyre (the choice of the Israel-Premier Tech team). The latter describes how incoming airflow is able to move past the forward-rotating wheel and tyre without creating pressure points or turbulence.

Exceptionally high grades of materials, including TeXtreme carbon, enabled the OSTRO to hit its weight target – earning it the VAM moniker shared with its featherweight sibling, the O2 VAM – while also delivering the stiffness required by the likes of legendary sprinter André Greipel, who raced an OSTRO in his final two seasons. “For most brands, the OSTRO would be an 1,100g frame or 40 per cent more expensive,” says Shrive.  

So, it was superlight, but was it fast enough? “I was actually surprised at the level of aero we were able to achieve,” says Shrive. “We tested as fast as the Cervélo S5 across a full sweep of yaw angles. I’ve tested everything and I know that’s the bike to beat. It was very close, but then the OSTRO is significantly lighter and now with the new bar, it’s outright faster.”  

Ah yes – a new iteration of the handlebar, designed with significant input from  Chris Froome, has just been introduced, saving an extra couple of watts. “We don’t wait for the next model cycle. It’s full gas all the time,” says Shrive.  

The level of involvement from Israel-Premier Tech is above anything you might expect. “We have a weekly call with the team and we’re in touch most days,” says Shrive. “Every time we go to the wind tunnel, three guys from the team join us. Rob really values long-term relationships, which is rare in the bike industry. We’re with Israel PT for the long haul.”  

Beyond its aero and lightness, the OSTRO is packed with bleeding-edge features. It’s made for disc brakes and electronic shifting only and routes the requisite hoses and wires fully internally past a D-shaped steerer which allows a regular 1 1/8” upper headset bearing for minimal frontal area. The bottom bracket uses the  excellent threaded T47 standard, the pencil seatstays borrow from comfort-oriented stablemate, the Vista, and the headset is CeramicSpeed’s maintenance-free SLT to remove any concerns about the fully-integrated front end and Black Inc one-piece cockpit.  

Black Inc is Factor’s sister brand for components and wheels. Inevitably, it’s viewed as an in-house supplier – and underestimated - but the level of engineering and performance stands comparison to the best on the market. The Forty Five wheels were designed to complement the OSTRO as fast, light all-rounders. “They’re as fast as most 60mm wheels and as stable as most 30s,” says Shrive. That sounds like an outrageous claim to make but they have the  data to back it up and, crucially, it’s borne out on the road, where they feel searingly fast and virtually immune to gusts. They’re laterally stiff, too, and respond to accelerations with vigour.  

Handling has not been overlooked, nor mirrored from industry conventions. The tight wheelbase and steeper head angle look aggressive on paper, but the OSTRO feels exceptionally balanced and confident in corners and it’s rock-solid stable at very high speeds on big descents. Three different fork offsets ensure consistent characteristics across all frame sizes.  

The pursuit of speed led Factor to what is now a close partnership with the friction killers at CeramicSpeed. The OSTRO uses their T47 bottom bracket and its Black Inc wheels feature ceramic bearings in their hubs. Additionally, this bike benefits from the (£350) optional upgrade OSPW (over-sized pulley wheels) for the rear derailleur.  While there is undeniable aesthetic appeal, it would be a mistake to dismiss it as mere ‘bling’ – you’ve never seen a drivetrain spin so freely at a standstill.

This OSTRO is in the ‘Flicker’ design that’s ridden by Israel-Premier Tech. It’s the lightest option (paint weight matters when you’re chasing every gramme) as there’s no paint, only lacquer over carbon and graphics. As well as being light  and looking great, you can see the carbon fibre lay-up. It wears its craft on its sleeve. Alternatively, there are several stock paint options, plus the possibility to create a custom design within a set of templates.  

I’ve been fortunate to spend most of this summer with the OSTRO, covering thousands of kilometres and climbing more than 50 mountains, including Rouleur's epic Explore ride. The OSTRO made a huge first impression and then, somehow, only went up from there. In every ride situation, it’s sensational.

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