Tour de France 2023 - 21st stage: Saint-Quentin-en-Yvelines - Paris | 115.1 kilometres
The grand finale in Paris is just around the corner. After an opening stage, the riders will complete eight laps of 6.8 kilometres on the Parisian boulevard. The course is fast, easy to navigate and free of any major difficulties. The riders are fresh, as far as one can be after these three weeks. In any case, the stage itself is the easiest of the entire Tour de France. It's a bit of an exhibition race plus an hour of hard cycling. The main difficulty is the muck riders: the final sprint is particularly prestigious and therefore fiercely contested.
In several issues of this newsletter, we have outlined what you need to do to be technically well equipped for sprinting. First and foremost: be aerodynamic.
Tour de France 2023: Sprint on cobblestones
Things are no different on the Champs Elysees. 700 metres before the finish, the last bend has to be negotiated, where a sprinter has to be in position, then it's straight on towards the finish line. The sprint takes place on relatively smooth cobblestones. With 28mm tyres and adjusted air pressure, which is what most riders use anyway, the surface is easy to control. However, ultra-soft tyres without puncture protection, as is the case with many time trial tyres, are not recommended on the inner city course. Experience has shown that the risk of punctures is higher there.
As the number of the day, however, we're not looking at the sprint but back to Tuesday's time trial - the 16th stage of the 2023 Tour de France. In our briefing, we predicted a winning time of 32:56, which Jonas Vingegaard beat by 20 seconds.
We had advised against changing the wheel. Most of the riders did not. But co-favourite Tadej Pogacar changed his bike, which took around 14 seconds. According to our calculations, this did not give him an advantage, on the contrary. He lost 34 seconds to Vingegaard on the core climb, and Vingegaard's aero and power advantage came to the fore as the climb flattened out. Here the Dane made up massive ground (-43 seconds). Pogacar certainly didn't have his best day, but he also didn't have the best strategy to grab yellow.
Vingegaard said after the race that he had held back on the flat part of the course and pedalled 380 watts. Based on this information and the course data, we calculated his cwA value.
Number of the day: 0.18 square metres
Everyone could see that Jonas Vingegaard was sitting quickly on the bike. His head was completely in front of his torso. Based on the split times, our model of the route and the information provided by Vingegaard, we calculate his cwA value to be 0.18 square metres.
That is an absolute world-class value. We only know of one lower published value. The American Colby Pearce, former American hour record holder, was measured at 0.1656 - but in his specialised discipline on the track, not comparable to a road race in the Tour de France.
The cwA value is the product of the frontal area and the cw value; it describes how aerodynamic an object is. The lowest possible values should be aimed for. Normal cwA values for very good time drivers are around 0.195 square metres.
However, this absolute top aerodynamics was only one component in Vingegaard's winning ride. He also took high risks on the descent, had the right pacing and material strategy and put in an extraordinary amount of power. All of this together resulted in the fabulous time.
That brings this year's tech briefing to a close. I hope it was entertaining and gave you an insight or two into the technology behind the great performances of the stars. See you next year!
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.
