Tour de France 2023 - 16th stage: Passy - Combloux | 22.4 kilometres (individual time trial)
The only time trial of the 2023 Tour de France is coming up. And it is special, just like the rest of the Tour, especially in terms of the route. In the first section, the route has a short ramp, but is then slightly downhill and fast until it climbs steeply from kilometre 16, 2.5 kilometres at 9.4 per cent. The rest of the route is briefly flat and then continues to climb at 5.6 and 5.9 per cent (average: 4.7 per cent).
So it's a combination of a flat time trial and a mountain time trial, as we saw recently at the Giro d'Italia. In contrast to the course at the Giro, however, the steep section is shorter and not super steep. This raises the question for the teams: change bikes? Yes or no?
Various options
Without question, the time trial bike is the faster bike up to the start of the steep section. Changing to another bike takes at least 10 seconds, but can also take 15 or 20 seconds. Can this be achieved with a lightweight bike? Or do you mount a time trial clip on the road racer and save yourself the wheel change?
We don't have as much hard data on time trial bikes as we do on road bikes and have to work with estimates to work out which setup is fastest in the conditions mentioned.
As usual, we model the route in detail and let our digital pro ride the different configurations and compete against each other. We use 15 different time trial bikes for the 16th stage of the Tour de France 2023 with different weights and aerodynamic qualities. TT 10 to 12 seems to us the most likely configuration. Under these conditions, the TT bike is clearly faster than a road bike with clip-ons.
Number of the day: 1:11 minutes
The simulation shows that a TT bike (TT 11 configuration) is 1:11 minutes faster than Tadej Pogacar's road bike accelerated with clip-ons. Time trial bike (TT) or road bike? An overview of the calculated riding times without changing bikes - the arrow marks the most likely configuration from our point of view:
Would a wheel change make a difference on the 16th stage of the 2023 Tour de France?
We simulate a bike change at the start of the steep climb. Result: Tadej Pogacar would lose at least 20 seconds in total (10 seconds change time calculated) - this is all based on the premise that his pedalling performance on the TT bike is comparable to that on his road bike.
*) 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 also 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.
