Aerodynamics and its Dynamics

We have always discussed about many things on our rides besides technical know how's and bike tech. So here's some techie insight to going aero.

Aerodynamics plays a huge role in the bicycle world and more so especially on road bikes.

Many different wheel manufacturers have different R&D methods and tricks up their sleeves. Notable houses include the likes of Zipp, HED Cycling, and Enve Composites, not forgetting Madfiber.

A lot of wind tunnel testing has been done to make sure that most of the wheels perform under varying real world wind conditions to ensure stability and ease of handling.

Why so much attention to wheel sets you may ask. This is because the next most important drag inducing component on a bicycle after the frame is the wheel set where spokes and surfaces such as the tire and depth of the wheel generates turbulent airflow which in turns increases drag. This equates to you churning out more watts (effort) to maintain forward motion.

Of course we cannot do anything to streamline the rider of the bike apart from donning tights and suits which are fitting to reduce drag.

But what manufacturers can do is to make aero road legal frames which have seen hundreds of hours in the wind tunnels as well as come up with wind cheating wheels to compliment the bike.

That's why you will notice that aero wheels play an important role in races where every mili-second counts.

The amount of effort and R&D put into the wheels also means that we will have to pay a premium to enjoy the aero benefits.

Do note that the majority of the effects of aero wheels can and will only be felt at speeds of 30kmh and above as anything below that has no significant effect on drag and speed.

Having said that, up till today, aero wheel manufacturers have more or less targeted a specific frame manufacturer and have come up with wheels which are catered to fit only certain bike models from certain manufacturers.

And usually on a road bike, the front and the rear wheel depth is the same.

Interestingly, manufacturers such as ENVE Composites are debunking the theory that wheel sets should be specifically tailored only for specific brands.

They have come up with their own set of front and rear specific wheels which can be used on any regular bike frame regardless of make.

So consider the facts and benefits that you will gain before going to make that pocket-burning purchase. Otherwise, stick to good old proven training wheels if you think that aero is still a long way to go! hehe!

Apart from having the best equipment and a well maintained bike... here's an interesting explanation by Aerodynamics guru - Steve Hed.

Aerodynamics is the study of how a solid body moves through the air . So when we relate that definition to the sport of cycling, it's about how a rider and machine overcome air resistance created by forward motion and the prevailing wind. The lower the resistance, the faster you go.

At 25mph, 80% of an average rider's power output is used just to overcome the effects of wind drag when riding on the flat. Any reduction in this percentage results in either an increase in speed or a decrease in effort.

The speed you can achieve on your bike is determined by two factors. The first is how much power you are able to produce, measured in watts. The second is wind resistance, commonly referred to as "drag" and is usually measured in pounds at 30 mph in wind tunnel testing. The faster you go, the more wind drag there is to overcome. This is why a rider with a technical advantage is often able to go faster than one with a greater power output.

It's a relatively simple matter to design an aero wheel capable of producing a low drag factor against a direct headwind. However, we understand that a true zero degree headwind is almost unknown on the road. All it takes is a 5mm lateral shift by the rider and the headwind becomes a side wind in relation to the front wheel. Designing a wheel that performs well in all wind conditions is therefore paramount.

By carefully regulating the depth and shape of our wheels, we can achieve optimum wheel performance no matter what the wind conditions happen to be. When our numbers go down in the wind tunnel, you go faster out on the road.