Timing for
Endurance
Races

In endurance races such as 24-hour, 12-hour or similar formats, teams share vehicles and swap drivers throughout the event. The biggest challenge for any timing system is not the duration itself, but managing vehicle and driver changes without compromising the standings.

How it works in RaceControl

RaceControl supports team races and endurance events. You can assign multiple drivers to a single vehicle, or multiple vehicles to the same team, and the system keeps individual lap times and team standings updated at all times.

This removes the transponder logistics that typically lead to errors, delays and disputes. With RaceControl, driver swaps are completely transparent to the system.

How to perform a driver relay

A track operator, from a phone, tablet or the computer itself, selects which kart is coming into the pits and which one is going out. If the driver is also changing, it can be specified in the same step.

As soon as the new vehicle crosses the finish line, the system automatically merges the team results. Laps completed, fastest lap, lap history... everything is unified with full accuracy. As far as the standings are concerned, nothing happened. The new kart number appears immediately on the scoreboards, so what you see on screen always matches what is on track.

From that point on, the kart that came into the pits is free and can be reassigned to another team later.

What happens if I miss the relay

In endurance races there is a lot at stake, nerves run high and track staff are stretched to the limit. Sometimes it is simply not possible to keep up with race control due to other priorities. If a kart goes out on track and you did not register the relay in time, or even if you picked the wrong vehicle, you can undo the merge and redo it up to several laps after the new kart has been racing.

How it was done until now

Traditionally, an operator has to remove the transponder from the vehicle coming into the pits and fit it onto the new one. It seems straightforward, but it can cause delays that are completely out of the operator's hands. Your pit stop time ends up depending on how smoothly that swap goes. Even though over the course of the event you will get fast and slow swaps alike, in the moment it creates a lot of tension.

There is also a tracking problem with this method. When you move the transponder, the new kart goes out on track carrying the identity of the previous one. For example, you go out in kart 6 but on screens and results you show up as kart 1. It reaches a point where neither staff, spectators nor the teams themselves know who is who. Following the race becomes impossible.

Nassau panel swap

Some tracks mount the transponder on the nassau panel of the kart. When a relay happens, the team swaps the entire nassau panel, and with it the bib number and the transponder. This way the visible number always matches what the system registers and the race can be followed without issues. On top of that, the swap is performed by the team itself, so whatever time you gain or lose depends entirely on you.

It is a very effective method. The only downside is that it requires special transponders, usually more expensive and battery-powered, capable of working at a greater height than conventional ones. You also need your entire kart fleet to have nassau panels with a quick-release system.

Advantages of using the app or the laptimer displays

We are not reinventing the wheel here. Laptimers are already routine in practically any race or endurance event, whether as an app or on dedicated systems. Almost all of them run on high-frequency external GPS and give you lap time, sector splits and delta. Very useful information for learning a track, polishing a specific corner and correcting on the fly.

While the result is near perfect in most cases, GPS has limits that cannot be dodged. The internal receiver in the phone itself is almost always short of the accuracy required, and in both cases a mixed layout with covered sections, a tunnel or nearby hills and buildings introduce position errors, dropouts and wrong lap times. At an indoor track there is simply nothing to be done.

And there is something more fundamental. All of that loses value once the driver knows the racing line. Beyond a certain level the information they need is not in the delta, but in what is happening around them... how far ahead the closest rival is, how much of the session is left, whether there is a yellow flag, whether they have picked up a penalty or whether the team needs them to come into the pits. A traditional laptimer cannot get there, because it only measures itself.

That is where the RaceControl laptimer module comes in. The information is not calculated by the device, it is sent by the official race timing, so the times are exactly the ones that appear in the standings and they come down to the thousandth, with no dependence on GPS coverage or on what is overhead. With the app there is no investment for the user, because the driver opens it on their own phone. You can find the detail on both options on the timing software page.

Communication with the team

In an endurance race the driver needs constant feedback, and this is where it shows most. From the pit wall, the team follows lap-by-lap progress and can send messages to the driver's screen. When a message expects a reply, the driver answers with a single tap using the preset quick responses, a yes or a no, without typing and without taking their attention off the track. There is also two-way voice, which the driver opens with the on-screen button or from the headset button itself.

With the steering wheel displays the messages work the same way, with certain advantages, such as the physical buttons or better daytime visibility. In this case it is the track that has to provide the hardware and its prior installation.