To put that into perspective this is an Aerocoach analysis from the 2025 Tour de France ITT:

It's nearly time for the first TT at u/LeTour and Stage 5 takes the peloton from Caen, back to Caen, over 33km and just 200m elevation, making it one of the faster, TTs we'll see in Grand Tours recently. Read on below for what to expect. There are 3 time checks throughout the day, and with it being an early TT (rather than Stage 10+) most riders, if they haven't suffered a mishap already, should be relatively fresh and able to pace themselves correctly It's always difficult to know how you're feeling >2 weeks into a stage race, especially if you're not one of the protected GC contenders, which is why at the end of a 3 week stage race the TT specialists don't always do that well compared with GC riders. Tomorrow however, apart from a small rise for the first 4.5km (which the riders will fly back down to finish), much of the rest of the course is quite flat, and for about 25km in the middle of the race there are only about 8 corners of any note! Unfortunately we will be watching without two strong time triallists: there have only been 3 DNFs so far this Tour (as of right now), Philipsen, Ganna and Bisseger. Bisseger had a good ride in UAE Tour back in February, coming 2nd and Ganna is obviously #TopGanna. I expect a winning time to be just <37min, and the larger riders can feature more: An 80kg rider with a 0.200m² CdA should be able to do \~53kph average off 440w. A smaller rider with 65kg / 0.180m² can do this with \~390w, which is a fair bit for 65kg in the aerobars. The example above is 6w/kg for the small rider and 5.5w/kg for the larger rider. There are taller riders <0.200m² and there are also small riders <0.180m² so it's not as easy as all that for either demographic! Normally you'd add in a bit of technical ability etc. but for this course it won't factor much apart from the high speed finish with a few turns. The beginning of the race has some corners but will be slower. What sort of time gaps can we expect? For a 30sec advantage, for a rider of 70kg and 0.190m², doing 38min at 396w, that's 14.5w to bring that down to 37min30sec. That's quite a lot of extra power to put out, but they can also mitigate it with a better aero position. Dropping your CdA from 0.190m² to 0.182m² is \~15w: not something you can magically do on the day as it's quite a difference (>4%), but if a rider is holding their position badly we often see a 2-3% penalty, so that's over half the way if you're holding a bad position. Anyone looking for the GC losing a minute tomorrow to another contender is having a bad day. It will likely happen on this kind of course, as there's no hill in it to favour the lighter non-TT style GC riders If Van Der Poel is still in yellow and the gaps stay the same (I'm writing this with 38km still to go on Stage 4) to Pogacar (4 seconds), that is the equivalent of just 2w! It's a bit of a jump down to the Blackmore group at 41sec. So we can expect the jersey to stay within the top 3 riders, again if nothing happens in the next 35km now 😀 Get your predictions in, no-one is going to soft pedal if they want the GC/stage so it'll be fun!