Cycling aerodynamics: are aero fairings a waste of time?

For fans of road cycling, it’s virtually impossible to escape the topic of aerodynamics. The whole industry is obsessed and practically every new bike is released with bold aero claims.

Even our own GCN Tech presenters are guilty of it, constantly reminding everyone of just how important aerodynamics are.

In pursuit of any aero advantage, many riders and brands use things called aero fairings on their bikes, but what are they, and how much of a difference do they actually make?

According to GCN’s Alex Paton and Ollie Bridgewood, they make a big difference, and they wanted to prove it by putting some aero fairings to the test.

Did the results back up their pro-aerodynamic beliefs?

Let’s find out.

What are aero fairings?

Fairings are shells or covers that can be added to bikes to alter the flow of air over it, helping to minimise drag. They function in a similar way to aero helmets, creating a better aero profile.

From Bianchi’s unique Air Deflector Wings to integrated bottle cages, aero fairings are used throughout the industry, but you won’t see any in pro bike races. That’s because cycling’s governing body, the UCI, banned teams and riders from using them.

© Bianchi

Bianchi’s Oltre RC bike has an aero fairing on its head tube.

Whilst pros can’t take advantage of them, everyday riders can, and they definitely should, according to Alex and Ollie.

The only way to definitively prove their point was to put aero fairings to the test.

The test

As always, our dynamic duo came up with a flawless (mostly) test. Alex rode four laps of the Odd Down Cycle Circuit in three different set-ups:

• The first was using a normal set-up with a standard, non-aerodynamic water bottle.
• The second was using Orbea’s aero water bottle and storage unit. The Spanish brand claims that these aero fairings save three watts when riding at 50 kph.
• And finally, they took things to the extreme with an aero windscreen. It’s something you’d more commonly see on a motorbike, but could it also be an aerodynamic solution for road bikes too?

For each test, Alex used an Orbea Orca bike and attempted to ride in the same position for each. He also averaged 221 watts for the three efforts, so which one ended up being faster?

Aerodynamics mythbusting: Most modern road bikes are released with aerodynamic claims, and brands will often say that their bikes are X watts faster at X kilometres per hour. The speed provided is usually between 40 and 50 kph, which doesn’t seem very applicable to everyday riders. That figure isn’t ride speed, though, and actually refers to the air speed. In the above example, Orbea claims that its fairings make the bike faster at 50 kph. That 50 kph is equivalent to someone riding at 30 kph with a 15 kph headwind, so it’s much more applicable to everyday riders than you may first think.

The results

The moment we’ve all been waiting for. Did Alex and Ollie prove their point?

Here are Alex’s times for each set-up:

• Standard set-up: 10:48
• Aero fairings: 10:40
• Aero windscreen: 10:56

It’s good news for our presenters as Alex went eight seconds faster when using aero fairings compared to the standard set-up. Unsurprisingly, the aero windscreen caused more drag, resulting in the slowest time, and we don’t expect to see new bikes specced with one of those anytime soon.

Of course, these are only small differences, but over a longer ride those advantages become much greater.

So, should we all be using aero fairings? It depends.

Many cyclists aren’t bothered about speed, so those lost seconds don’t really matter. But for anyone who is performance-oriented and regularly on the hunt for added speed, aero fairings could be the way to go. 

There’s plenty more research and development that still needs to go into aero fairings and Alex and Ollie already have some ideas for future tests, including a potential return of the aero windscreen. Watch this space!