To talk about aerodynamics first we have to understand air and its density. Let’s make a real life example. To reach 130 kph we need approximately 15 hp like from a 125 cc. While to get to 200 kph we need at least 70 hp. To reach 300 kph we need 170 hp. That means two and a half times the power to go a third faster. You’ll understand pretty soon how air actually matters and at some speed the air feels dense like water. So with the increase of speed, in the 50s, had to find a way to “pierce” the air.
A Brief History of Aerodynamics
After WWII the US banned Italy, Germany, and Japan from producing aircraft. This caused to bring all the engineers in the car and motorcycle industry giving them a big leap in technology progress.
In 1950 every motorcycle brand was working on their fairings but Moto Guzzi raised the bar in aerodynamics development. They built the world first real size wind tunnel and refined their dustbin fairings (yes, that’s the name, don’t ask). This aerodynamics solution was working as aspected on the straight line increasing the speed and lowering fuel consumption. But having such a big flat surface attached at the front of the bike caused side wind to be difficult to handle and in some occasions even dangerous. So in 1958, the racing commission decided to ban them.
Farings reappeared immediately afterward but much tighter. Between the 70s and the 2000s, we’ve seen dramatic changes concerning the tail. It was small in the beginning then vertical and flat like the tail of an airplane, big and round like the 1998 Suzuki GSXR 750 and short and thin in the 2000s. But the big change came in the last two years after Ducati introduced the winglets in MotoGP. There is a lot of confusion about how they work so I think it’s time to move to the next section and get technical.
Let it flow
You might think that a motorcycle being smaller than a car has a better drag coefficient. If so, you’re wrong. It’s actually worse than a van and the reason why is the rider. The fairing pierces the air the laminar flow to slip over the body but as soon as it reaches the edge the air finds a vacuum and doesn’t really know where to go and what to do. These uncontrollable streams are called turbulence. The leather suit designers tried to reduce turbulences by putting an aerodynamic bump on the back of the rider that fits perfectly with the shape of the helmet. But that’s the only aerodynamic change they could make in the last 20 years on the rider’s suit. The shape of the fairings also evolved to improve the cooling system and top speed but the turbulence problem on a motorcycle is a bit like a lost battle.
The MotoGP solution
With the insane increase of top speed in MotoGP (in some race they reached 350 kph), the teams needed to stabilize the bikes somehow. The winglets don’t have the same function like the ones on a racing car. They don’t really have the same downforces because bikes lean into a corner and this changes the angle of work on the bike. If it’d apply the same forces like on a car steering the bike into a corner would be incredibly hard. This is also confirmed by the riders feedback who could find little differences or, in some case, none.
The winglets were there to bring stability to the bike in acceleration. The MotoGP race commission decided to ban them for safety reasons even though Ducati was ready to officially demonstrate that they were safe. Another technological solution banned from MotoGP won’t be a brake for progress and engineers, so how will the fairings look like at the first race in Qatar?
I hope you enjoyed this “how to” and that you have a better idea of aerodynamics. If you like this article please share it with your friends.