Why hasn’t a drafting detection system been developed for Ironman races till now?

Due to the design, unfortunately it won’t also double as a wheelsucker detector for weekend warriors

Aero
(Image credit: Future)

In Ironman racing (opens in new tab), the question of drafting is a thorny issue. The crux of the sport centres on an almost masochistic, herculean effort (opens in new tab) – anything which stands to detract from that is, naturally, a complete anathema. 

And of course, you wouldn’t wish any of your co-competitors the chance of inadvertently diminishing their own efforts either.

With this as the context, two New Zealander triathletes, James Elvery and Dylan McNeice, sought to develop an accurate, reliable and consistent method for detecting and highlighting drafting in draft-illegal triathlon races (opens in new tab), which make up the majority of events.

After six years of R&D, the Duo’s RaceRanger system is set to be used in select races through the first half of 2022, with full scale use in mass, age-group fields (over 3,500 athletes) planned for spring 2023.

So how does the RaceRanger work?

The bike of each competitor gets equipped with two sensors in a similar way to how timing chips are already mounted. The first sensor is attached to the fork leg, while the second is placed underneath the saddle.

When you reach a set threshold distance behind the rider in front, say, 16m (52ft), your front sensor will communicate with the rear sensor of the front rider and will display a slow, red flashing light indicating that the sensor has registered your presence, but that you’re still in the safe zone.

Edge closer, and you’ll end up crossing a second threshold at, say, 14m (46ft). Then, the signal changes to a rapidly flashing red light, warning you that if you get much closer you will enter the drafting zone.

Once you come past the 12m meter mark (which is World Triathlon’s common rule), the light changes to blue and the flashing becomes more rapid - with a single red flash repeating every 5 seconds. This alerts you that you’ve entered the drafting zone and now have 25 seconds to make a pass or face a penalty.

Now, the RaceRanger doesn’t completely automate the task of policing drafting - the discretion of race officials will still be needed at times. There may be sections of the course where athletes end up bunching through no fault of their own, such as at the foot of hills or through twisty town centre streets.

But it does have the potential to greatly boost the officials’ abilities to keep a handle on drafting.

For organisers to offer the system at their events, extra money will have to be raised - which will increase the entry fees. Initially, the RaceRanger system will only be offered for Ironman distance events, as the percentage price increase would be proportionally smaller than in shorter – and cheaper – events. 

Currently, each unit of the RaceRanger system weighs 85 grams – for comparison, a Garmin Varia RTL515 radar bike light (opens in new tab) weighs 100g. The casing has been designed to minimise the aerodynamic impact, although naturally, there will be a penalty. But as everyone in the race would be using the system, this is unlikely to have an impact on the outcome of the race.

Thank you for reading 5 articles this month* Join now for unlimited access

Enjoy your first month for just £1 / $1 / €1

*Read 5 free articles per month without a subscription

Join now for unlimited access

Try first month for just £1 / $1 / €1

Stefan Abram
Stefan Abram

Starting off riding mountain bikes on the South Downs way, he soon made the switch the road cycling. Now, he’s come full circle and is back out on the trails, although the flat bars have been swapped for the curly ones of a gravel bike.


Always looking for the next challenge, he’s Everested in under 12 hours (opens in new tab) and ridden the South Downs Double in sub 20 (opens in new tab). Although dabbling in racing off-road, on-road and virtually (opens in new tab), to date his only significant achievement has been winning the National Single-Speed Cross-Country Mountain Bike Championships in 2019.


Height: 177cm

Weight: 67–69kg