A quick look at the 13.8km TT on Stage 1

Typical TT Wattage for the Pros2015 Stage 1 TdF Rohan Dennis
A TT is always a balance between power and aerodynamics. Folding yourself into an aero position on a TT bike inevitably sacrifices a few watts (usually in the order of 10% or so, but with significant differences from rider to rider). A pro who can comfortably produce 400w for 20mins on a climb (in a comfortable position sitting up with the hands on the top of the bars) may only produce 360w in an aero tuck. This is highly variable between riders depending on their flexibility and build.

Stage 1 TT
For this TT on Stage 1 we were looking at a time around 15mins and the fastest TT riders (usually a little bigger at 75kg or so) are likely producing around 450w (around 5.5w/kg) or so in an aero position, although it is not so much power to weight as it is power to frontal surface area and aerodynamic drag. In comparison, a typical A grade rider the same size could be in the low 300w range in an aero tuck. Wiggins doing an individual pursuit is around 560w for 4mins.

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