Vuelta TT preview – is GC Kuss real?

Sepp Kuss is currently in red going into the TT on stage 10 of La Vuelta. It’s a bit strange, no one expected him to be in the race lead but – if he can get through tomorrow, he has the class in the mountains to win GC. Remco is 2:22 down on the American with Kuss’ Jumbo team mates, Roglic and Vingegaard on 2:29 and 2:33 respectively.

The TT is only 25.8km in length so, while we all expect these gaps to close, the chances are Kuss will still be in the race lead unless Marc Soler or Lenny Martinez pull a really great TT out the bag. Sepp Kuss’ time trial ability has rarely been tested in the past but we all know that Jumbo can execute a good TT when they want to. 

The time trial is only 25km long but we saw in this year’s Tour de France that short time trials can create big gaps but this time trial is, for all purposes, completely flat. This both benefits Sepp Kuss and hinders him. The benefit comes from the fact that not much time can be lost during a medium length flat TT as the speeds are high, however relative to the rest of the GC contenders Kuss is one of the better climbers – and his TT ability remains unknown… 

The forecast

Two things of note come up when thinking of this course, firstly it is basically pan flat and secondly there are a few technical sections. This time trial is essentially a test of watts and cda though – you’ll see riders who have spent time in the wind tunnel will have a big advantage – but more on that later. The main takeaway here is that the course is relatively simple and suits the pure TT specialists.
The race conditions are also relatively trouble free. Here we’ve put some numbers in to represent your ‘average’ grand tour rider and you’ll notice that the ground speed is extremely high for this power. These high speed conditions will suit Remco Evenepoel over his GC rivals and it will also suit Ganna for the stage win. The conditions remain favourable throughout the day and are quite stable seeing no shift greater than a couple of seconds due to weather. That said, this could be the time separating stage winners – look out for that in our Vuelta TT Review.
This plot shows us the effective wind that riders will feel during the course of their TT. These extremely shallow yaw angles show us that a rider will feel the wind mostly on their front and back. This is a relatively simple wind direction distribution and will suit the GC riders that haven’t done a great deal of testing or are experienced time trialists. Simply put, there’s less to be gained by knowing which wheel is fastest in crosswinds vs headwinds which is knowledge some teams will have that others don’t. These simple conditions equalise the TT somewhat.
While this course is flat, there are parts of it where power will matter more than others. There’s a few steep ramps at 3km and just before 6km. The orange bars on this plot show us where inputting a decent amount of power will have the most return on investment. The most interesting instance is the orange bar just before 8km. This is a portion of descent that flattens out and pushing hard on this section before the road drops down again is an energy investment that leads to more speed being held on the lower part of the descent.

CdA and Time

Other than Jumbo and Sepp Kuss, I don’t think anyone knows if he’s spent any time in the wind tunnel. I’d imagine some rudimentary testing has been done but the question of how aero Sepp Kuss actually is seems to be a little bit of a mystery. Apparently, he’s 61kg with an FTP of 383W (this might be nonsense though, I just found it reported online somewhere) but let’s put these numbers into myWindsock and see how varying the cda impacts the time.

It’s clear that aerodynamics makes a huge difference on this course with time spent in the wind tunnel being worth almost two minutes on this course. Sepp Kuss will hope that he’s aero enough to maintain his position on GC. It’s clear he has the power to do a great time trial though. Aerodynamics won’t be a priority for Kuss who primarily rides as a mountain domestique so his time will depend on two factors – how aero he naturally is and how fast Jumbo’s equipment is.

Remco vs Ganna

As well as the GC drama there’s the prospect of a stage win up for grabs. Let’s estimate some times for Remco Evenepoel and Pippo Ganna to see who will come out on top using what we think we know about their various numbers.

Remco’s predicted time is on the bottom, Ganna’s on the top. These numbers are estimates and the time prediction can of course change with the weather but we notice two things – Ganna’s weather is marginally more advantageous and the course suits him slightly better. The official myWindsock prediction is that Ganna will win the stage… just.