The battle against overheating: how the teams cool their fuel and bikes

Last weekend, it was evident with some teams: with temperatures approaching 40 degrees, they were refuelling their motorbikes with chilled fuel. To prevent the fuel from warming up again in the tank before the start, Lucas Coenen’s factory KTM, for example, was fitted with heat-insulating mats. Jeffrey Herlings’ Honda was prepared for the heat battle in an even more extreme way.

Changing bikes before the start

Jeffrey Herlings completed the formation lap on his spare bike. The race bike was parked behind the skybox and was kept cool with a battery fan right up until the start. The fuel tank, which was filled with chilled fuel, was wrapped in damp cloths, and the clutch housing was kept cool with an ice pack. After the formation lap, Herlings switched to the cooled-down bike, which had the added advantage of giving him fresh tyres without having to change them. The bike was started as late as possible. Herlings took the holeshot and won the first race.

Tank-Isolationsmatte an der Werks-KTM von Lucas Coenen

Foto: copyright free

What are the benefits of cooler fuel?

Warm fuel has a lower density and therefore also a lower energy density. Put simply: the same volume of fuel contains less energy at higher temperatures. Warmed air also has a lower density than cooler air and therefore contains less oxygen. This is precisely what costs power.

Cooling the clutch

The clutch is under the greatest strain during the start phase. According to unconfirmed reports, Herlings’ retirements at the German Grand Prix and in Latvia were caused by overheated clutches. In Montevarchi, the HRC crew tried to cool Jeffreys’ Honda clutch down as much as possible with an ice pack, particularly before the start. The clutch and the bike held up, and ‘The Bullet’ was able to celebrate his 116th Grand Prix victory.