Tour de France 2024 - Stage 5: Saint-Jean-de-Maurienne - Saint-Vulbas | 177.4 kilometres
After the climb up the second highest mountain of the Tour, the fifth stage is back to flat fare. The sprinters in the peloton will have marked this day as another opportunity. The two fourth-category mountains will hardly stop the sprinters' teams from preparing a fast finale, as there are still 30 kilometres to the finish from the Cote de Lhuis, which is only 383 metres high.
The approach to the finish is clear again. Wide roads lead into the city, the last 2,000 metres are mostly straight ahead. 250 metres before the finish, the 6.5 metre wide finishing straight makes a slight bend to the right. The home straight climbs slightly: there is a difference in altitude of four metres between the Teufelslappen and the finish line.
How much aero is necessary?
From a material point of view, the matter is clear: an aero bike is the measure of all things here too. There are also new additions to the peloton. A new, rather extremely shaped aero bike has appeared from van Rysel, although the team's all-rounder, the van Rysel RCR Pro, already has good aero characteristics. The 7.2 kg van Rysel RCR Pro was measured by TOUR at 207 watts, which is at least two watts faster than the hyped Specialized Tarmac SL 8, which is even lighter.
Nevertheless, Decathlon, supplier of the Decathlon AG2R La Mondiale team, has not missed the opportunity to put an apparently even faster bike on the wheels, which will certainly be used on the fifth stage. We don't have any measurements of the bike, but it can be assumed that it will be even faster, otherwise why would the team pursue a two-bike strategy? The benchmark for super aero bikes in the TOUR test is 200 watts. So far, only the Simplon Pride II has fallen below this (199 W). However, this bike will not be at the start of the Tour de France. We are curious to see whether the still nameless Aero van-Rysel will be able to break into these regions.
In contrast to Decathlon, Trek has recently adopted a one-bike-fits-all strategy like Specialized. The Americans have lightened the new Madone and scaled back the aero tube shapes; the Trek Emonda lightweight bike has been cancelled, at least in the Carbon variant. According to Trek, the new Madone has lost nothing in terms of aerodynamics, but has become significantly lighter. We had Jasper Stuyven's new Madone in size L on the scales and were able to measure 7,650 grams ready to race - not a super light bike. How the aero performance is under TOUR conditions remains to be seen. As long as we have no data on this, the Madone SLR 9 remains in our list for comparison.
For the finish of the fifth stage, we simulate a very short sprint of just 150 metres. Which bike from our list has the front tyre in these conditions?
Number of the day: two thousandths of a second
Once again, Canyon snatched first place and secured it by a mere two thousandths of a second ahead of the Cervelo S5, whose weight we corrected downwards after weighing it in the paddock ready to race at 7.6 kg (Christophe Laporte's bike, RH 54).
Canyon's mathematical lead has therefore narrowed. This shows that every tiny detail counts. Especially when several tiny details come together, they have a cumulative effect. We predict a top speed of just over 70 km/h in the short sprint.
The (almost) entire field at a glance*
*) 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.
Aero rules: The mathematical ranking almost reflects the aero ranking. As acceleration also plays a role in the last few metres, weight is not completely out of the equation in sprinting. If in doubt, the sprinter's bike should therefore be as light as possible. Especially if the sprint is short, as in our simulation of the fifth stage.
The importance of aerodynamics has been confirmed by the course of the Tour so far. The breakaway victories on the first two stages were won with aero material. The fact that Romain Bardet and his team-mate were able to successfully fend off the peloton on the first stage and take the yellow jersey for one day was also due to the fact that he had a fast bike at his disposal with the Scott Foil RC (206 W). Bardet, a climber by nature, fought the decisive battle downhill and finally even flat with a headwind. Further aero anomalies of the first days: Jonas Vingegaard favoured the fast S5 over the lighter R5. He was able to capitalise on this advantage on the second stage, in the "pair time trial" with Tadej Pogacar, when the two of them distanced the field.
On the third stage, Biniam Girmay from Intermarche-Wanty on the Cube Litening AeroC:68X prevailed against Mads Pedersen on the new Trek Madone. Girmay's timing was certainly more important than his aero bike, but when you're riding at the front, every little helps to increase your chances of victory. Our prediction is therefore: aero bikes will not completely merge with lightweight bikes. Where an advantage can be realised, it will be sought, found and implemented.
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.
