2026 Tour de France Tech Briefing: Climbing specialists should join forces

​The world’s best cyclists will be competing in the Tour de France until 26 July. Victory and defeat on the roads of France are decided not only by the riders’ legs, but also by their equipment. The TOUR Tech Briefing for Stage 18.

Stage 18 has an unusual profile for a mountain stage. There are no fewer than 3,800 metres of climbing to tackle, but only two climbs really stand out: the Côte d’Engins right at the start and the final climb to Orcières-Merlette, which doesn’t look particularly difficult (7.1 km, 6.7%).

We expect strong climbers in the breakaway to pull away, whilst the GC contenders will be saving their energy for the final stage at Alpe d’Huez.

​We’re simulating a long attack by a lightweight climber who goes on the offensive right from the first climb. Which bike would be ideal for a long solo breakaway on this stage? And what role does the fact that our hypothetical climber weighs just 58 kg play in this?

Number of the day: 6 minutes 42 seconds

​The analysis shows that, despite the significant elevation gain over the entire route, aerodynamics play a decisive role. Cervélo’s S5 is once again the ideal bike for a long breakaway – with minimal weight and top-class aerodynamics. The lead over the Cervélo R5, the slowest bike in the field, is 6 minutes 42 seconds. But even compared to the second-fastest bike, the S5 already gains 31 seconds. The conclusion: details matter, and bikes designed purely for lightness have hardly any use left.

However, the analysis also shows that a solo attempt by a very light climber is unlikely to be successful. They lack the power to maintain sufficient speed over the distance.

It is far more likely that a group will break away. By drafting, it is possible to maintain a significantly higher average pace even on this mountain stage.

Climbing specialists should therefore team up and only battle it out amongst themselves for the stage win on the final climb. Otherwise, they are highly likely to be caught by the GC riders, even if the latter aren’t riding at full throttle.

An overview of the (almost) full line-up*:

​The table shows the ride times for a 160 km ride. Aerodynamic wheels come out on top in the rankings – even though the calculations are based on a very light rider

​* Simulation calculations

Based on our own wind tunnel tests, we carry out simulation calculations for the Tour de France tech briefing. How TOUR tests: Aero road bike test in the wind tunnel.

We are investigating which wheels can offer a technical advantage in which situations. The variables we can control in the simulation include wheel weight, rider weight, the inertia of the wheels, the drag coefficient, the rolling resistance coefficient and the efficiency of the drivetrain.

To model ride times, we use realistic power outputs and weights for the riders, combine these with our wind tunnel data, and have the riders race virtually along selected sections of the route, which we extract from the official route data; the derived elevation profiles are key to this. The modelling also includes bends, which we can brake for realistically, and adjustable power profiles for different types of riders. This allows us to distinguish between attacks on climbs and proper final sprints. Taken together, this makes the simulation very realistic. What we cannot replicate are dynamic handling effects such as the individual behaviour of the wheels on different surfaces.

The journey times calculated for the sections of the route that are decisive for the race highlight the influence of the wheels – provided that the riders always behave in the same way in a given scenario.