Sky team had the Bolide version, equipped with extensions, a made-up proto wheel (800 g estimated from some research!), Conti Pro LTD tubulars, KCNC light quick releases, chain lubricated at the last minute with Muc off hydrodynamic (there were still
blue traces). In short, an ultra-high-performance and light machine, Concerning the Sallanches approaching 7 kg, it’s difficult to find a better compromise for this time trial (the weight of the frame + fork kit is 1.4 kg, very close to the F8).
The advantage of a disc rim on
50 mm rims at different speeds…as it was a day with little wind and given the
low mass of the prototype, it was not necessary to deprive ourselves of it in my opinion…
Froome wins the stage and Romain Bardet finishes 42 seconds behind. I think that Froome was not better
than Bardet that day (or very little)…but that his equipment and Concerning the Sallanches his qualities as a rider
made the difference.
A time trial for climbers, but not only…
Bardet had chosen his classic bike equipped with simple extensions and Zipp 303 wheel. The Focus does not appear in the table where
the Ultimate and the classic frames appear but we can think that with its round tubes,
it is rather around 230 w of drag (like a Cube or Cannondale). It would therefore lose 25 watts on the rolling sections at 45 km/h to which we can add another 10 watts lost on the disc wheel + 3-spoke aero of the Bolide at Froomey.
For example, the FDJ team had chosen the Aerostorm chrono frame option and certainly T.Pinot (sniff..) would have used it like A.Roux below.
Position in search of speed just before the slope of the Poex road (15%)
We have a more telling example of aero gain in a pass with
a rolling section thanks to the Bikesplit site, specialized in numerical calculations: the EZE pass from Paris to Nice.
The choice was based on the comparison between a Treck Emonda (with or without extension) and a
Treck Speed concept.
The Emonda version needs 20 watts more to achieve
the same time as the Speed Concept despite the Emonda weighing 1.5 kg less