It’s bad news for Filippo Ganna, the Ineos Grenadiers, and other exponents of the not-at-all-obvious ‘marginal gain’ of stacking a team car with bikes and driving right behind your rider during a time trial, as the UCI has moved to extend even further the minimum distance permitted for following cars during the race of truth.
As we noted on the live blog after Ganna’s controversial win at last year’s Critérium du Dauphiné, the position and shape of team cars – aided by an unnecessary raft of bikes strapped to the roof – has become an all-important consideration for squads willing to push the limit during individual time trials.
Although we usually associate aerodynamics with the airflow over the cyclist from the front, effectively, teams can get a push effect by stacking the car in that rather incongruous way and following their rider at close proximity.
Back in November we reported that, along with a raft of other rule changes related to equipment and rider positions, the UCI had moved to counteract this aero benefit by stipulating that from 1 January all team drivers would be required to remain 15 metres behind their charges during races against the clock.
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Now, following further consultation, the sport’s governing body has decided to increase this minimum distance even further to 25 metres – in order, the UCI says, to “ensure that the presence of vehicles does not have an effect on the performance of the cyclist”.
“Furthermore, the 25m distance aims to increase rider safety by providing the driver of the vehicle with longer reaction times in the case of an unexpected mishap or incident,” the UCI added in a statement released today.
Race convoy vehicles, such as TV motorbikes, photographers, and those belonging to commissaires, will still be permitted to drive closer to carry out their roles, but must stay out of the direct slipstream of a rider to mitigate any potential aero gains.
So, why 25 metres?
Well, the UCI said that according to a study carried out by the Eindhoven University of Technology in the Netherlands, the presence of a car 10 metres behind a rider gives them an advantage of 0.05 seconds per kilometre at a speed of 46.8 km/h – equating to one second in a 20km time trial.
Increasing the distance to 15m and beyond, the study found, renders that advantage insignificant.
“This new rule aims to ensure that the results of time trials are not influenced by the proximity of the rider to the following vehicle and thus to guarantee the sporting fairness of the competition and increase rider safety,” says the UCI.