One of the big topics that comes up when you are looking to get into time trials and triathlons in cycling is aero wheels. Wheelsets on bikes are an expensive upgrade, in fact in most cases upgrading your wheelset is frequently more expensive than your entire bike! This is especially the case if you are just upgrading your road bike to get into triathlons. So why are aero wheels faster? In this article we will break down some of the science behind this question to better help you make the call on if an upgrade to aero wheels is right for you!
If you look around for the physics behind aero wheels you are going to find a lot of highly physics based articles, which are very equation heavy. My goal here is to simplify that information and provide just the hard facts.
Well to put it simple your biggest acting force against you while you are riding a bike is wind. Every cyclist knows this. It is why we do as much as possible to improve our aero positioning and get products that will also reduce this drag.
In the case of wheels, the only coefficient in the equation that is affected is the drag. Which is dependent on the shape of the object that air is passing through or around.
So as you can expect with this the more aero that the wheelset is, the easier it will be for wind to pass around the object and thus will improve your race time.
What occurs then with this equation is by reducing the drag on the bike it allows other aspects of cycling to improve, such as your speed and cadence. This equates to not only faster times but also the decreased input will allow you to ride for longer intervals for the same effort.
Concluding these aero wheels definitely are faster, by the aspect that they decrease drag thus improving your power and speed. The next question that then crops up though is, how much faster are aero wheels and are they worth the cost?
In this video which is just an example of aero performance
A rider with standard wheels rode for a duration of 20 minutes at about 25 miles per hour and used 379 watts of effort.
The same rider transitioned to a pair of Zipp Wheels and rode for 51 minutes at the same cadence but used only 344 watts of power.
As you can see from this example. The major change was not a massive improvement in speed but the rider was able to ride for twice the duration using less effort and maintain the same speed!
This is a huge benefit for any endurance athlete that is needing to ride for longer distances, such as Ironman length races.
In closing, on why are aero wheels faster? Aero wheels are faster due to the reduced drag they contribute to your rides. It is definitely something however that benefits anyone riding for distances but probably not as necessary for sprint athletes unless you are truly trying to compete at the top levels. Aero wheels excel at shaving seconds off your time and more importantly saving your legs for the run in triathlons as you will have to use less watts of power to maintain the same level of speed.
Additionally they are not something you have to break the bank for! You can get some very affordable aero wheels if you are looking for your first entry pair. Or you can go high end with brands like Zipp and Eagle Wheelsets.
Every step you can take to make you more aerodynamic is going to help fight air and get you across the finish line!
Hey there, my name is James and I am the creator and editor of this site. I have been doing Triathlons for a while now and am competing in 70.3 Ironman's as well come this year. I created this site to help those new to the sport and to share my journey with other athletes.