Tour de France 2024 - Stage 10: Orleans - Saint-Amand-Montrond | 187.3 kilometres
It doesn't get any flatter: on the way to Saint-Amand-Montrond, there are only 950 metres of elevation gain to climb on the 10th stage - there are also molehills over 187 kilometres. On paper, it is a stage in which Mark Cavendish could add another victory to his 35, especially as he already won here on 12 July 2013. The finishing straight is 500 metres short, with four bends to negotiate between the Devil's Lap and the 500-metre mark. Clever positioning is therefore even more important than usual, which suits Cavendish's riding style.
If there is a strong wind, it could have a say in the open plains and cause the field to split into wind stacks. If a strong wind blows from the side, the riders experience what our wind tunnel dummy experiences every day: the wind does not hit the riders head-on, but more or less diagonally from the side. The riders then stagger diagonally across the road. With this staggered riding style, the slipstream can be maximised when riding diagonally. Only the rider at the very outer edge of the relay then works hard. Fast circling can create a hole in such a slipstream.
This is because the riders at the end of the relay are "taken on the edge of the wind" - anyone who no longer has a place in the relay is just as exposed as the leader of the relay. However, the difference is that there is no breakaway. This is why the field usually breaks up at the end of the relay. Riders who are left behind form new relay teams. As a result, the field breaks up into small groups. Teams that are on their toes and have a good weatherman who can accurately predict the wind direction sometimes provoke this effect, quickly forming a wind relay team when changing direction and surprising their rivals.
The main effect comes from a clever riding style, but you can also use technology to help: Aero road bikes and aero wheels offer the greatest advantages in strong winds. Sail-friendly front wheels can even be driven by the wind. An optimally equipped team can make all the difference. If your head, legs and equipment work together perfectly, you can make a lot of time even on an unimpressive course.
Number of the day: 10 seconds
Tempo ride on the wind edge: a 10-second lead over five kilometres is possible through cycling technique alone - if we compare the aerodynamic with the less aerodynamic bikes. In reality, the achievable gaps are greater because motivation and riding technique have a greater effect than cycling technique.
The (almost) entire field at a glance*
*) The calculations are based on the bikes tested by TOUR in the laboratory and wind tunnel. The bikes at the Tour de France may differ in some details. Of course, we have not yet been able to analyse last-minute prototypes. Background to the simulation.
The table shows the riding times over five kilometres when a team attacks hard. Aero bikes pull out a lead.
Gravel review
Just like on the wind edge, a tactical overview was also required on Sunday's gravel stage. The top riders also experienced how quickly a gap can develop. Once poorly positioned, Primoz Roglic was suddenly over 30 seconds behind on the second gravel section. In the end, however, the top teams defused all the crisis situations, Roglic's gap as well as Jonas Vingegaard's flat tyre, who finished on the bike of his team-mate Jan Tratnik. Visma | Lease a Bike showed a remarkably good team performance, rode confidently from the front and had obviously put on thicker tyres than usual. Tadej Pogacar attacked as expected. Ultimately, however, the course proved to be too easy to simply ride away from everyone, especially as Vingegaard behaved purely defensively and showed no interest in getting away from his team. As a result, nothing happened in the overall classification.
Top aero values of the stars
We would also like to take a brief look back at the first time trial. Remco Evenepoel's winning time beat our fastest simulation time by two seconds. This is a strong indication of how crazy good Remco Evenepoel's aerodynamics are. We had calculated with an average of just under 400 watts, a performance that Evenepoel had already achieved two years ago in a time trial at the Tour of the Algarve and (very briefly) documented on Strava before the entry was deleted again. An aero power of 205 watts for a speed of 45 km/h therefore seems absolutely realistic, which corresponds to a cwA value of 0.175 - a dream value and the key to top performances.
That aerodynamics are the key to his success can also be deduced from the fact that he cannot keep up with the very best on the climbs, despite his relatively low weight. His physique seems ideal for time trialling. His upper body lies behind the massive aero helmet, which together with his arms directs the airflow around his body. But the other top riders also looked very, very fast. Roglic saved the time trial with a very fast second half, which also speaks for good aerodynamics and downhill technique - both important factors in view of the final time trial after Nice.
Our expert
Robert Kühnen studied mechanical engineering, writes about technical and training topics for TOUR and develops test methods. Robert has been refining the simulation calculations for years and they are also used by professional teams.
