The likes of Team Sky, Movistar and Sunweb spend huge amounts of money and man hours refining their aerodynamics. But as you’ll discover, there’s more to it than plonking Froome and Valverde in a wind-tunnel…

"I wore a skinsuit in 1984 in a road race in the UK when I wasn’t even 16 and got absolutely ridiculed in the changing rooms for wearing it. Then I pissed the competition off by winning. Now you won’t see any time-triallist wearing anything but a skinsuit. I still think we have a fledgling understanding but there’s definitely been a culture shift when it comes to cycling and aerodynamics."

The words of Christopher Miles Boardman when I asked the man known as "The Professor" for his meticulous attention to detail how long he’s been interested – nay, obsessed – with aerodynamics or, in other words, riding faster for no extra effort.

Boardman’s slipstreaming fascination continues to this day, most recently seen with the opening of the Boardman Performance Centre on the edge of the Cotswolds.

As well as offering physiological and biomechanical assessments, the 18,000 square-foot facility houses what’s arguably the UK’s first ‘accessible’, cycling-specific wind-tunnel. I visited recently and it’s damn impressive, with Boardman’s Everyman plan costing from £195.00 for one hour to £695.00 to a four-hour aero extravaganza. ("I wanted recreational riders to use a wind-tunnel for the price of a curry", he said).

Okay, that’s one pricey vindaloo but you can see why Chris and many of his fellow aero enthusiasts are singing to the same aero melody - around 80% of your drag comes from you, 20% from your bike and its parts. Reduce the impact of both and arguably you’ll enjoy greater gains than spending two-grand on a lighter wheelset.

It’s why every WorldTour team – we’re talking Sky, Movistar, AG2R La Mondiale etc – spends a good portion of the ‘off-season’ either in the wind-tunnel or circling the velodrome in search of aerodynamic gains.

Specific rider and gear data remains behind closed doors but, thanks to the likes of Chris Yu, Director of Integrated Technologies at Specialized, we’ve been given an exclusive insight into how the world’s best will seek aero advancements this winter…

Refining the rider's position

"We have what’s called the Specialized Racing Departmental Programme, which works directly with riders", explains Yu.

Specialized currently provide bikes and other gear for Peter Sagan’s Bora-Hansgrohe, Astana and Quick-Step Floors. "We not only provide the equipment but the means to figure out the best way of using equipment specific to the goals of a team and athlete for that particular season".

An illustration of this is seeing how Specialized would work with a GC rider like Quick-Step’s Enric Mas, who finished a surprising second at this year’s Vuelta a Espana.

"Say he’s targeting July’s Tour de France...as soon as the route is announced, we’ll begin dissecting how rider position and equipment can benefit the rider on the specific parcours" said Yu.

"Say we had a scenario where there’s a critical time-trial in the middle of the race, which is undulating and about 40-45km, we’ll calculate how we can optimise their aerodynamics and power output for an hour’s riding".

"We’ll start in the wind-tunnel – at Specialized we’re fortunate as we have our own , the Win Tunnel – and we’ll spend two days analysing that rider. Even for riders of their quality, they’re tempted to hit extreme positions because the numbers improve, but if you can’t hold that position for very long, it’s worthless. In this instance, we’d need to hold it for an hour".

Yu and his team will not only focus on the TT position. To maximise resources they’ll examine the rider to ascertain his most aerodynamically optimum position on the drops, hoods and tops for a range of different stages.

"We’ll then send him away to ride at home and have follow-up sessions in January or February, but this time it’ll be via on-the-road and velodrome testing. Essentially, we retest those positions but in a slightly different environment where they’re racing their bike at race power".

Using aerodynamic gear

As we’re sure you’re aware, wind-tunnel time isn’t solely focused on bike position. Wheel, bike, helmet and bike-clothing manufacturers all secure wind-tunnel time with the aim of making their products more aerodynamic (and to give their marketing teams something to shout about when it comes to advertising of course!)

Take Sportful, who made a big song and dance about spending £300,000 developing a skinsuit specific to Alberto Contador’s body shape, utilising fabrics and material placement to smooth out airflow and send the Spaniard scything through the air with effortless speed. It worked, his time-trial time dropped.

Alex Dowsett is one of the world’s best time-triallists. He briefly held the world hour record in 2015 and currently rides for Katusha-Alpecin. He told us his technique of constantly shrugging his shoulders brings them inward and makes him more aerodynamic.

That was down to working with aerodynamicist Simon Smart when he raced for Movistar (and we've got an exclusive interview with Simon if you're interested in learning more).

He’s also adopted higher outer edges to his arm rests, which provides something to press against when pulling those shoulders in. In fact, Dowsett’s a great exemplar of the recent aero focus that’s been less about getting as low as you can go and more about narrowing the frontal profile.

"Things have certainly come on", he told us. "I remember Rod Ellingworth [Team Sky’s High Performance Manager] looking at my bike at the national championships in 2013, almost sneering at my handlebar set-up and saying I gave away 30 seconds to [Bradley] Wiggins when I won the Giro TT because there were cables everywhere. I was also using an old set of bars that hadn’t been updated in a while. It was frustrating to hear but I'm now in a much better position and use much better gear as a result".

Field testing everything

Dowsett’s experience is not unique. Notoriously poor time-triallists Nairo Quintana and Romain Bardet have improved their weakest discipline over the past two years specifically due to data gathering, better equipment and the growing use of field testing.

"We complement wind-tunnel sessions with track and road testing", says aerodynamicist Xavier Disley, who’s worked with GrandTour winners but can’t name names.

We can say that he helped develop the NoPinz aerodynamic suit, worn by Lotto-Jumbo NL, the design of which caters for the fact airflow over your lower back is entirely different from the airflow over your forearm or front of shoulders.

"We use the Garmin Track Aero System. It’s a hardware and software suite, and provides the session analyst with the riders’ aerodynamic drag wirelessly every second as they ride around the velodrome. We conduct track sessions abroad but mainly work in Derby and Newport Velodromes in the U.K. It forms a vital part of the aero testing triad…".

Disley completes that triad with on-the-road aerodynamic assessments, using customised software that analyses wind and atmospheric conditions to calculates the rider’s drag.

Specialized also test the WorldTour riders out on the road thanks to a number of technological advancements.

"As well as traditional sensors and tools like power meters and speed sensors, we load what we call “modules’” onto the top tube,’ Chris Yu explains. "One is an infra-red laser module that tracks the torso and head while the rider is pedalling. The other is a lean angle sensor, which measures how much the rider is swinging the bike.

All these sensors feed information to a box on the bike, which is sent to a server. We can monitor it trackside or, if I’m not there for some reason, I can pick it up here in California and watch things in real time on a computer".

This combination of wind-tunnel time, velodrome feedback and road testing continues apace, with developments like the Boardman Performance Centre arguably the next step in the aerodynamic evolution.

By cutting costs, both professional and recreational riders will be able to spend more time in the wind-tunnel, further refining their position as their strength and stamina improves. And even for wealthy teams like Team Sky, saving money without sacrificing knowledge, gains and the racing edge is key.

Take CFD (Computational Fluid Dynamics). This involves measuring the air resistance of different shapes and has already transformed how experts design and create bikes, as well as impacting bike position and even how riders ride together.

"When testing team time-trial situations on CFD, as well as out on the road, not only did we find some riders are better suited behind others to minimise overall drag, the leading rider enjoys a drag reduction of around 3.5% from the rider behind", says Disley. "That’s something to think about the next time you’re berating your club mates for not taking a pull on your next Sunday morning ride!’