Tour de France 2025 - Stage 1: Lille - Lille | 184.9 kilometres | 1150 vertical metres
The start of the Tour de France is classic and leads exclusively along French roads. The start is over 185 predominantly flat kilometres to and from Lille. The expected finish is a bunch sprint. The last mountain classification of the day is in the fourth category and lies 45 kilometres before the finish. With fresh legs, the sprinters will probably iron out the Mont Noir with the big blade (1.3 km, 6.4 %). And if one of them does get dropped, there will be plenty of time to get back to the front with the help of the team.
As always, everyone is motivated to the max at the start, which leads directly to the biggest unknown of the day, namely the risk of crashing. The width of the road is finite, everyone wants to ride at the front, everyone wants to win something, the classification riders at least don't want to lose anything. This is the setting for a lot of speed and even more nervousness. It is unlikely that a group will get away given these conditions. It is almost impossible that they will get through. The most likely scenario is a big crash that could tear the peloton apart and influence the outcome of the race.
What does that mean for the bikes? And what is the starting position for the material in this Tour de France? This briefing will focus on cycling technique and the interactions between material, route and tactics.
Comeback of the aero bolides
Last year, it looked like designers were increasingly trying to build bikes that would make it easier for riders to choose the best bike for each stage. All-round racing machines such as the Specialized Tarmac SL8 represent this type of bike. Very light, aerodynamically good, but not as streamlined as the aerodynamically fastest bikes in the world. The advantage of the one-wheel strategy: less pondering, less effort (and cost), easier maintenance and always the same riding characteristics.
However, the lack of top performance of the all-round bikes did not make sense to all developers. Jean-Paul Ballard, aerodynamics expert from Swissside with an F1 background and consultant to the Decathlon AG2R La Mondiale team, argues that aerodynamics are the deciding factor in many riding situations. If you followed last year's briefing, you will have read that the most aerodynamic bikes usually came out on top in the simulations.
Van Rysel mixes up the peloton
Consequently, Ballard developed an even faster bike for Van Rysel. The new Van Rysel RCR-F Pro (200 W) saves a further 7 watts at 45 km/h in the wind tunnel compared to the also very fast all-rounder Van Rysel RCR Pro and is therefore presumably the aerodynamically fastest bike at the start of the Tour de France. In any case, it is the fastest TdF bike that we have been able to measure so far. At a sprint speed of 65 km/h, the aero advantage of the Van Rysel RCR-F Pro can triple from 7 to 21 W. The bike is also convincingly stiff, which is also a welcome bonus at top speeds. Disadvantages: higher weight (+ 600 g) and harsher handling.
Decathlon of all companies, relatively new to the World Tour and known to most as a sports discounter, is setting the technical pace in terms of aerodynamic optimisation in the Tour de France field!
Our prediction for the first stage: teams that have aero flounders in their repertoire will pull them and ignore the extra weight. Both the team helpers, who ride a lot in the wind and start the sprints, and the sprinters themselves will benefit from the best aerodynamic material on the course of the first stage. After all, one tyre width can decide who wins the stage and takes the first yellow jersey.
Visma | Lease a Bike will therefore unpack the Cervélo S5 and UAE will at least let the helpers toil away on the Y1Rs. Chef Tadej Pogačar hasn't ridden the bike much in the race. His choice of bike on the first stage is only a minor aspect in terms of performance. Nevertheless, we are curious to see whether he will start the Tour on his aero bike.
Number of the day: 0.005 seconds = 9 centimetres
In the simulated final sprint, Decathlon's new aero weapon is right at the front - despite a significant increase in weight. The calculated lead in a 200 metre sprint is 0.005 seconds or nine centimetres. Cervélo S5 and Canyon Aeroad, often the fastest bikes last year, follow in second place.
Colnago's new Y1Rs, which is aerodynamically worlds better than last year's winning bike from Tadej Pogačar, is also way out in front. We will dedicate a separate story to this in the next few days.
The (almost) entire field at a glance*
Our overview shows: Aero bikes are the best choice in the final first stage. In the sprint, they outperform the all-rounders and lightweight bikes, regardless of whether the minimum weight of 6.8 kg stipulated by the world governing body is exceeded. Top sprinters are also better served with the aero cuts if they add a kilo.
The calculation was made for a 75 kg driver.
*) 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.
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.
