Once upon a time the key metric for race-winning road bikes was weight, with riders, designers and drill-wielding team mechanics alike obsessively competing to see who could shed the most grams from their bikes in order to gain a competitive edge. Today however, ‘aero is everything’, with both wind tunnel research and real world results illustrating that when it comes to gaining crucial time on your competitors, bike and rider aerodynamics play a more significant part than weight on all but the toughest mountain stages.
The easier a bike can cut through a headwind, the less energy a rider expends and the faster he or she can go – sometimes only a matter of seconds over a race lasting many hours, but sometimes that’s enough to make the crucial difference.
Against this backdrop an entire sub-category of aero race bikes has emerged, typically characterised by shaped tube profiles that are designed to optimise air flow over the frameset. These are often teardrop in cross-section (as distinct from the round tubing of a traditional bike) with the blunt edge facing into the wind and producing an aerodynamic effect.
These are sometimes referred to as airfoil tubes owing to their cross-sectional resemblance to aircraft wings, or you might see a truncated version referred to as a Kamm-Tail. Think this sounds complicated? Let’s not even go there with triathlon, where the lack of UCI rules about such things has led to the evolution frame shapes that resemble intergalactic destroyers more than bicycles.
But we digress.
In short, aero road bikes are built for maximum straight-line speed, with aero tubing, deep-section wheels and often a large degree of component integration, always with the intention of influencing air flow over the surface of the machine and lowering drag. For many racers or competitive club riders they are the obvious weapon of choice, but bear in mind that they come with some compromises. All that additional material used for exotic tubes and deep-section wheels carries a little extra weight over a svelte climbing bike, and aero bikes aren’t much fun in crosswinds. In addition, bikes built for stiffness and speed also give away some comfort to their more endurance-intended cousins.
But if you’re a competitive rider on flattish courses, you’re athletic enough to adopt an aero position and you want to tip the scales in your favour, a slippery steed is the obvious choice, and the preference of most pros.
Read on for our guide to some of the best choices of 2020.
The complexity of aero bike design, involving high investment in materials and research, usually means that these bikes sit a little higher in the price hierarchy than ‘standard’ road or sportive bikes. All that innovative tube shaping takes time and expertise, and because carbon fibre is the frame material of choice (metal tubing being too hard to mould into aero profiles without adding significant weight), that comes with a price premium.
As too, do the quality components usually found on a bike that’s primarily intended for competition. That’s why it’s refreshing to find a quality aero ride like the UK-designed Orro Venturi Evo 105 Hydro carrying a price tag that’s well within the reach of most riders, without any obvious component compromises. New for 2020, this is a more wallet-friendly version of the Sussex firm’s top-drawer speed machine, kitted out with Shimano’s reliable mid-tier 105 groupset (hydraulic brakes included).
Vision Team 30 alloy wheels and some stylish Deda finishing kit. The frame is the star of the show however, made with a custom layup of 3 different types of UD carbon and featuring a wishlist of aero refinements including an hourglass head tube, shaped fork-to-downtube transition, rear wheel cutout, dropped seatstays, aero seatpost and hidden post clamp.
It’s also nice to see practical touches like clearance for 28mm tyres, making this a ride for every day rather than a race-day special.
Rondo bravely describe their HVRT as a true quiver-killer but for once that’s more than an idle boast – standout feature is the Polish company’s innovative Twintip adjustable geometry which allows the rider to switch from ‘relaxed off-road roamer’ to ‘aggressive podium predator’.
This is done by means of a removable fork insert which offers two positions – the first with steeper angles, smaller trail and a lower front end (so ideal for racing and fast road riding) and the second with slacker angles for endurance rides. However it’s not just adjustable geometry that gives this bike its USP – Rondo have designed the frame and forks with enough tyre clearance to fit standard 700c hoops and 30c tyres (in one setting) or game-changing 650b wheels and 47c tyres in the other. No longer do you need two bikes for on- and off-road action – with the HVRT series you just need two sets of wheels.
Also available in alloy and steel versions with more traditional tube profiling, this HVRT CF (for carbon fibre) comes with all the fancy aero features we have come to expect, including an aero seatpost, airfoil tubing, rear wheel cutout, dropped stays and more. Don’t be put off by it’s off-road potential, this is a proper aero race bike, just perfectly capable of morphing into a proper aero gravel bike when the mood takes it.
You can argue the toss about the merits of ‘women’s specific’ bike design all you want – and many would happily argue that limb length and torso dimensions have little to do with gender – but big bike manufacturers still market female-friendly versions of their marquee rides.
This, the Fuji Supreme 2.3, is the company’s effort to woo the women with a performance aero bike and actually, it’s very, very good. Described as a true Speed Queen, the Supreme underwent a radical overhaul in 2018, using wind-tunnel testing, 3D modelling and Kamm Foil truncated tube technology to create a bike that began racking up pro tour wins straight out of the gates.
For 2020 Fuji continues to reign Supreme, with the Ultegra-equipped 2.3 sitting in the middle of a three-bike range. We think it hits the sweet spot in terms of component quality and price, which is kept in check through liberal use of Oval Components, Fuji’s in-house parts brand. This is a fast, competent and balanced aero bike built with female riders in mind, and for that we’ll forgive the pink highlights on the paint job.
The Vitus ZX-1 may resemble a traditional road bike in silhouette, but don’t let that fool you – this is an aero-optimised speed machine with a T700 carbon fibre frame featuring Kamm-Tail tube profiles, a subtle rear wheel cutout and integrated forks and seatpost. It’s also a bike with an enviable racing heritage, the first generation ZX-1 dating back to 1991 and having been one of the first monocoque carbon fibre bikes in the pro peloton.
That original incarnation also featured aero tube profiling but it’s there the similarities pretty much end – this bike is bang up to date and laced with the latest technologies. For anyone with competitive ambitions the bike is fully UCI-approved, having been thoroughly race-proven in recent seasons by the Vitus Pro Cycling p/b Brother UK professional team.
The 2020 range features five models, with this ZX-1 CRS sitting pretty in the middle. We think it offers some of the best bang for your buck out there, boasting a spec sheet that includes 50mm Prime deep-section wheels, electronic Shimano Ultegra Di2 shifting and hydraulic disc brakes. That’s pro bike performance without the stratospheric price tag, whatever way you look at it.
Whereas the Vitus ZX-1 looks in passing like a more all-round road bike, everything about the new-for-2020 Cube Litening C:68X Pro screams aero – and so it should, the German brand having invested considerable time in tunnel testing and Computer Fluid Dynamics to reduce wind resistance and improve straight line speed.
Made from proprietory C:68X carbon and featuring a monocoque construction, the Litening is defined by an aggressive rear wheel cutout and buckets of aero integration across the chassis, fork, stem, handlebar, cables and seat post (there’s even an aero top cap).
All this adds up to a seriously slippery steed – with Cube claiming a 30% reduction in drag over the previous generation Litening which debuted in 2015, and positive media reviews finding little to fault.
This is the entry-level model in a four-bike range and offers good value for privateer racers.
For a sliver under four grand you’re getting not just that fast, hi-tech frame set but a full Shimano Ultegra Di2 electronic drivetrain with hydro disc brakes, plus a semi-aero 38mm alloy wheelset from Cube’s in-house component marque Newmen, helping to maintain manners in crosswinds.
The Fuji Transonic – cousin to the sprightly Supreme speed queen we met earlier – has been around for a few years now, being among the first mass-market aero road bikes to really gain a foothold among amateur riders and racers. For 2020 the Transonic upholds its own high standards and indeed has undergone a bit of a makeover, with Fuji taking some of the learnings from the success of the Supreme and applying them to its flagship speed machine.
But what does this mean, exactly? According to Fuji, it means replacing the rounded tubes on the previous generation Transonic with truncated Kamm-Tails, baking in a layer of additional comfort and adding touches like an integrated bar/stem and fully internal cabling.
Fuji buck the any-brake-you-like-as-long-as-its-disc trend by offering the Transonic in both disc and rim iterations (seven versions are available in total), with this Transonic 2.3 Disc again delivering solid value on the spec side. The Ultegra R8000 groupset offers mechanical rather than electronic shifting but is peerless when it comes to reliability and durability, while the Oval Concepts componentry sprinkled elsewhere on the bike keeps the price down and the performance high.
We are also somewhat smitten with the bold, confident Electric Blue paintwork – with so many aero racers opting for stealth colourways by default, we salute any bike that isn’t afraid to stand out from the pack.
De Rosa set cycling hearts a-flutter in 2016 with the introduction of the SK Pininfarina, an aero version of the Italian marque’s Super King model with input from iconic design house Pininfarina (more usually associated with names such as Ferrari and Alfa Romeo).
Four years later that collaboration has been reborn with a new version of the SK Pininfarina Disc, a seamless blend of style and function that surely deserves the tag of superbike. This is the kind of ride that inspires passion, with a more aerodynamic and lighter design than its predecessor but the same timeless sense of poise and style.
We note some subtle tube shaping refinements to clean up air flow, full internal cable routing and a modern revamp of De Rosa’s brand identity (the latter’s drag-reducing effect is unproven, but it definitely saves a watt or two).
Perhaps the most surprising thing about this De Rosa SK Racing 400 Disc model however is the value – for a collaboration between two venerable Italian design houses an off-the-peg price tag of under five grand is (whisper it) actually not that expensive, especially when stacked against some of its haute couture Italian peers. For the money you’re also getting much more than a sleek frame and the De Rosa name – full Shimano Ultegra shifting, hydraulic disc brakes and fast-rolling Fulcrum wheels mean this bike is built to hit the road, not parade down the catwalk.