Tour de France 2025 - 13th stage: Individual time trial Loudenvielle - Peyragudes | 10.9 kilometres | 650 vertical metres
The shortest stage of the Tour is coming up, the mountain time trial on the thirteenth stage. There are 650 metres of altitude to climb in just 10.9 kilometres. The start is tame, the second kilometre is even slightly downhill. After four kilometres, the gradient picks up. On average, the climb is 7.9% steep. The final climb to the Peyragudes airfield is particularly steep. For a short time, you have to pedal up 16%.
From a technical point of view, it is risky to cover the necessary gear range for this stage with a 1x12 gear ratio, as the speeds will range from 14 to 65 km/h. This would only work under the assumption that the rider can crank up the gears for a short time, which is unlikely at the end of the time trial. However, a cadence that plummets is not helpful either. A two-blade strategy is therefore likely.
Which brings us to the question of the best bike. The start of the course is fast, so a time trial bike has a clear advantage here. However, aerodynamics are not completely out of the question on the climbs, as the best cyclists reach almost 30 km/h in the flatter sections (6% gradient).
There are three strategies to choose from:
- Start on TT bike and change to road bike on the mountain
- Trim road bike with trailers to TT wheel and pull through with it
- Use conventional road wheel without trailer
To identify the best setup, we feed our simulation with our estimates for Tadej Pogačar. We don't know the exact data of his time trial bikes and the resulting overall aerodynamics. But we can make well-founded assumptions and run through some scenarios.
The number of the day: 11 seconds
According to our calculations, the fastest bikes are the time trial bikes. The TT11 configuration would save 11 seconds compared to a Y1Rs road bike retrofitted with extensions. Provided the time trial bike weighs 8.0 kilos. If it weighs 8.5, the advantage shrinks to 5 seconds. Without extensions, the V5Rs is the lightest option for Tadej Pogačar, but in our simulation it is slower than the V5Rs or Y1RS with extensions. The aero benefit compensates for the extra weight.
Pogačar has not had a good experience with wheel changes. A wheel change easily costs 15 seconds and interrupts the rhythm. Not an option for this stage from our point of view. We can't wait to see what strategies the teams have come up with.
The configurations for the mountain time trial at a glance
The table shows the calculated journey times for various configurations. TT11 seems to be a realistic scenario. This time trial bike would be slightly faster than the Colnago Y1Rs with an additional time trial attachment.
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.
