Personal aero meter
PERSONAL AERO METERS are changing how cycling performance is measured
It’s Day 1 of the 2018 Tour of Switzerland, an 18.3-km team trial trial starting and finishing in Frauenfeld – a small town in the Swiss canton of Thurgau – and the last major stage race before that year’s Tour de France. Astana Pro Team clips the line 1:18 behind first-place finisher bmc Racing Team. The Kazakhstan-registered outfit is second last. They have averaged 50 km/h on the hilly parcour; riders Jesper Hansen, Omar Fraile, Magnus Cort, Oscar Gatto, Tanel Kangert, Dmitriy Gruzdev and Jakob Fuglsang walk away disappointed, wondering what happened.
Later, retired engineer Marc Graveline gets a phone call. He has just stepped down from a company he helped start, Notio, which has recently developed personal aerodynamic meters for bikes. The company is partly funded by Argon 18, a bike manufacturer and Astana’s bike sponsor. The team has been using Notio’s Konect device for a while. Astana’s management is looking ahead to the Tour and asks Graveline to meet in Nice. Individual riders are performing well. Fuglsang, Astana’s leader, finished second in the Swiss tour general classification. The ttt, however, needs work.
The next day, Graveline is on a plane to France where he will spend the next few days testing the time trial squad’s aerodynamic drag coefficient, or CDA, to model for solutions. He uses the Notio Konect. As it’s able to calculate a precise road grade, angle of attack, road vibration, road resistance, mechanical resistance, hill resistance, wind speed, wind resistance, braking, acceleration, CDA and more, then combine that data with power, heart rate, speed, cadence and gps data, members of the team hope the little dongle on the Argon bikes might lead them to make changes – changes that could improve the ttt.
Graveline’s goals are simple: optimize pull times, keep the team together, maximize speed and power and have riders finish their next ttt with everyone’s tank completely emptied. He considers each rider’s weight; models “loss of time” associated with dropping back; and examines how to drop a rider or two at critical points without affecting the overall result. He then validates ideas using the Konect device, building contingency plans based on possible changes in the environment.
Graveline leaves the ad hoc aero camp days later. Using Konect, the team has identified, from Positions 2 to 8, who can stay at the front, for how long, and the time needed to recover, optimizing aerodynamics at every turn.
On July 9, at the first ttt stage at Tour de France in Cholet, Astana finishes eighth. (They were 20th at the Tour de Suisse.) The team has executed almost exactly to plan. According to Graveline, using the Notio data has empowered Astana to account for the physical world around each rider and enabled the team to find efficiencies – with gear, in positioning and with the time each rider spends at certain points in the rotation – which helped yield the result.
YET ANOTHER DONGLE
In 2016, Argon 18 introduced a concept bike at the Eurobike trade show that got people talking. Borrowing from aviation technology, company engineers put a pitot tube – a device that commonly measures different pressures affecting an airplane – in the bike’s head tube. With these pressures, you can get a plane’s airspeed, as well as altitude. The bike at the trade show – in all its beige splendor – turned heads.
“The idea was to combine the bike with the environment,” explains Martin Le Sauteur, Notio’s current chief executive. “A lot of people are tracking what’s happening on the bike, power or heart rate, for example. The concept was about the measuring the environment the cyclist was working in to account for the forces the rider is up against.”
At that time, the push toward frame tech was accelerating. Argon’s sensor didn’t measure watts, however, as was the focus for many of its competitors. Konect accounted for the world around the rider, and in realtime. The pencil-like protrusion on the Argon frame was a panacea; data-philes would now have access to data historically reserved for tunnel tests. For Astana, and for cyclists everywhere, it promised to be what the power meter was not too long ago – a Holy Grail of information that lay untapped previously.
Measuring CDA accounts for air density, humidity, rolling resistance, wind speed and more. But unlike wind tunnels, the Argon bike measured in real conditions and therefore provided much more realistic models and recommendations. The concept bike at that year’s Eurobike, the ces for bike gadgetry, seemed to put the possibility for gaining more speed with the same or similar watts within reach.
Engineers inside Notio say aerodynamics factors into approximately 80 per cent of the opposing forces a rider fights on a bike. A cyclist going 36 km/h pushing 200 watts on a flat course has a CDA of approximately 0.28. If the rider could improve that CDA by 10 per cent and drop it to 0.252, generating that same 200 watts, the cyclist would go 37.5 km/h. Bettering the CDA still, say, with a measure of 0.205 (considered an elite output), a rider could go 40 km/h with the same power numbers. The pitot tube attached to a bike can also help to isolate each variable – tires, helmets, kit, bike fit and more – for testing. Interest in the product was immediate.
By 2017, Notio had a niche product for which it had to create a new market. The company soon realized the real opportunity was in creating a universal bit of hardware, adaptable to any bike, not just Argon’s. The first prototype incorporated all of the sensors that were first introduced on the concept frame. Similar to when Ulrich Schoberer of srm designed, manufactured and submitted a patent for the first spider-based cycling power meter in 1986, Notio was about to change cycling performance with Konect, or so they thought. But just like early iterations of power meters, Konect yielded data few platforms (or people) could understand. The adoption curve looked sloped, not steep.
Personal aero devices have never been done before. Garmin has hinted at developing one; the company currently offers extensive track aerodynamic testing and has acquired technology that will likely be added to its own ecosystem, but nothing exists today that mimics the Konect hardware. For Notio to move beyond theoretical speed and the streams of data outputs, platforms such as Goldencheetah, Trainingpeaks and the like need to be able to make sense of Notio’s information and synch it with other biometric details. An app such as Strava, for example – to which eight million activities are uploaded per week – can show a fraction of Konect’s full capabilities. Users who want the device’s full benefits have to go deeper.
While Notio has already broken through with early adopters (including pro teams such as Astana, serious triathletes and engineers), management acknowledges it needs to make its data more digestible to gain wider use in the cycling community. Anyone can buy a Konect today (for US$950), sure. But the company will sell it (at time of writing) only with an accompanying three-hour user training. Making sense of the data would be a struggle otherwise. There are simply too many data points for most users to wrap their heads around. (In Spring 2019, Notio expects to launch an updated app that will make data interpretation less difficult. The company thinks that will then broaden the device’s appeal.)
ESTABLISHING A GOLD STANDARD
Harm Ubbens is a sports aerodynamics specialist at Bike Valley in Belgium, which features a wind tunnel facility, and works with Lotto Soudal, Ridley and several other product manufacturers. Talking about the Konect, a device he has not used but has examined online, he sees a space for personal aero devices in cycling. Admittedly, he says, he is biased. Tunnels will always offer one thing the Konect cannot: controlled environments. For product testing, where shapes and moulds stay the same, that is likely the best apples-to-apples comparison for speed.
To standardize and optimize data, a combination of outputs are needed. Road, tunnel and track environments all have their own benefits. They also have margins of error that researchers such as Ubbens have to take into account.
“Tunnels,” he explains from the Belgian facility, “might not offer the same degree of freedom of movement as a road or track environment, but what they do offer are controlled variables that allow for accurate outputs.”
Asked about a future where personal aero devices are
“If the rider could improve that CDA by 10 per cent and drop it to 0.252, generating that same 200 watts, the cyclist would go 37.5 km/h.”
used exclusively, he believes each testing environment is slightly imperfect. A rider who has trouble on the track, for example, won’t get the full benefit of aero testing when riding on the road. Weather is also constantly changing, adding variables that further complicate data analysis.
To have the best chance of improving aerodynamics, he says, riders need a combination of data sets. Where devices like Konect can excel are by giving riders the ability to do more frequent checks on positioning and to rely on tunnels less. But getting CDA information on the road still requires deep data processing to validate the numbers.
WHAT THIS THING REALLY NEEDS IS MORE AERO
After a bike is lighter, stiffer and faster, has upgraded wheels, Ceramic Speed bearings and oversize rearwheel pulleys, Chris King hubs, a power meter and all the rest, what’s left to upgrade? How do you go faster after you’ve maxed out your available training hours? Gaining 20 to 50 more watts might come down to owning a personal aero meter, say the folks at Notio. It’s a simple matter of positioning. After adopting the Konect, Astana have moved almost exclusively to aero testing on a track using the Konect, says Hugo Houle, a classics and individual time trial specialist riding for Astana. The benefits are significant.
“Thinking back on 2015, I was going a lot on feeling,” says Houle about the year he won both the itt at the Pan American Games and Canadian championships. “Things have changed dramatically with Konect. They’ve gotten much more technical, but also a lot more fun. We can see the impact of being on a teammate’s wheel. We can see which helmet is faster, which skinsuit works better. It’s like being in a tunnel, but more realistic.”
Like power meters, getting the most from an aero meter puts the onus on the person analyzing the information. Astana has hired a dedicated engineer to test all of the team’s product and analyze aero data – a luxury most cyclists can’t afford. Precise analysis requires downloading and deep interpretation of data files. Houle and others continue to experiment with the real-time display of CDA, which, he says, is the real value of the Konect’s output when it’s displayed on a Garmin – but that too has its limitations. Currently, no existing bike computers support the display of aero data (real-time CDA); it is only enabled on Garmin devices through Notio’s Connect IQ app. An update to ant+, coming in 2019 according to Le Sauteur, is expected to solve compatibility problems between Konect and most bike computers.
Argon 18 will presumably bring the advances made by Notio back into its bikes, furthering its own ambitions and industry demand for technological integration beyond what seemed possible when it first introduced that concept bike back in 2016. Piling on to Astana’s ttt turnaround, five other professional cycling teams have reached out with interest to use the Konect technology, adding to the company’s momentum.
When comparing Notio’s device with tunnel tests, it seems obvious interest will continue to spike, both at the professional and enthusiast levels. Wind tunnels require cyclists to sit in place, almost still, to gage aerodynamic efficiency. They also require lots of money. Once riders can see the gains that Konect can offer easily – like power meters before it – it is only a matter of time before the technology hangs off more bikes. Soon you’ll start getting “kudos” for holding watts longer into a headwind. The gains might come as a result of training, sure. But with the Konect or devices like it, at least you’ll know the true nature of your improvements.