Aero tucks and marginal gains to make a difference in Tour Down Under prologue
Rule clarification from UCI allows aero tuck position on road bikes
The men’s Santos Tour Down Under starts with a 5.5km prologue time trial on Tuesday, with riders looking for every marginal gain that could decide the stage winner and gain them precious seconds in the battle for overall race victory.
The UCI, teams and race organisers have agreed that the time trial will be contested on standard road bikes for race logistical reasons but that decision has highlighted a lack of clarity in the UCI rule book and so created an opportunity for teams to bend the rules and find a possible marginal gain.
Disc wheels and aero helmets will be allowed but time trial bikes and aerobars of any kind are not allowed. However after questions and debate in the pre-race meeting with teams and UCI race officials, Cyclingnews understands that riders will be allowed to go into some kind of aero tuck or 'puppy paws' position by racing with their forearms on the tops of the handlebars.
Rohan Dennis (Jumbo-Visma), Ethan Hayter (Ineos Grenadiers) and Michael Matthews (Jayco-AlUla) are amongst the favourites for the prologue time trial. The time trial will decide the first race leader and set-up the battle for overall victory.
A clarification of the UCI rules for the Tour Down Under prologue was sent overnight by Michael Rogers, the UCI’s Head of Road & Innovation.
Rogers cited rule 2.2.025 (Conduct of Riders - Position on the Bicycle) in a message to Cyclingnews.
"It states: Riders must observe the standard position as defined by article 1.3.008. Sitting on the bicycle’s top tube is prohibited. Furthermore, using the forearms as a point of support on the handlebar is prohibited except in time trials."
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The only condition regarding the aero tuck position is that riders must also touch their brake levers or hoods with at least their finger tips to respect the UCI rules.
It is unclear how the UCI will monitor every rider during the time trial and if they will sanction anyone who is seen in the aero tuck without touching their brake hoods.
Teams that Cyclingnews spoke to are well aware of the aerodynamic advantages of the aero tuck position but are disappointed there is little clarity in the UCI rule book for time trials contested on road race bikes.
It also remains to be seen if riders will take the risk of going into the aero tuck positions on the twisting course. Some of the straight sections of the 5.5km course will make the aero tuck beneficial but riders will be racing at 50km/h and have had little time to test the position in training or out on the course.
The full benefits or risks of the aero tuck position will only emerge during the time trial and perhaps be measured in the final stage results.
Teams are also looking for marginal gains in other areas, with some riders using tri-spoke front wheels along with their disc-brake rear wheels. However it seems not every team has disc-brake disc wheels.
The weather could also offer a marginal gain, with wind expected for the early starters, while a risk of rain showers later in the race could massively affect rider performance.
Several teams have opted to place their team leaders in the middle of the start list to avoid the extremes of the weather.
Nobody wants to crash in a prologue time trial before five days of intense racing and there are also concerns about the smooth surface on the long bridge that takes the riders from the start ramp out onto the course.
Cyclingnews will have detailed live coverage of the time trial, a full stage report, photo gallery, interviews and analysis of the racing.
Stephen is the most experienced member of the Cyclingnews team, having reported on professional cycling since 1994. He has been Head of News at Cyclingnews since 2022, before which he held the position of European editor since 2012 and previously worked for Reuters, Shift Active Media, and CyclingWeekly, among other publications.