Aerodynamic Efficiency and understanding the goal;

Bikes have become money pits in 2024. The equivalent bicycle to what I ride (A Felt AR with Ultegra Di2) is $9,000 new, and the cheapest option in that line is $3,500. Now, you do get quite a bit for that money; electric shifting, thru-axles, carbon fiber everything, electric shifting and hydraulic disc brakes. But, fundamentally, my frameset is a 2017, and in 7 years not much has changed.

The research and development on aerodynamics and materials science has reached a ridiculous level with bicycles today. The cost of the hours of wind-tunnel and computational fluid dynamic (CFD) analysis ends up borne by the end consumer, and it seems there is not a shortage of people willing to blow money on these highly refined versions of the same bike you could ride 10 years ago.

Formula 1 is an open wheeled racing series where aerodynamics has become a critical science for performance. There are 10 teams who design and build their own car, within a rule set, and then race it 20 times for a championship. Wind tunnel and CFD use had become so expensive in the sport that rules needed to be introduced to reduce the amount such that smaller teams could compete fairly; teams with more money had such an advantage with wind tunnel and computer resources that it was impossible for smaller teams to come close to the performance of the few leading teams.

Now in Formula 1, there is a trade off in aerodynamic performance between drag and downforce. Aerodynamics are used to develop the greatest amount of downforce, which improves cornering performance, with the least amount of drag. As such, aerodynamics are similarly marginal to bicycles. Every tenth of a percent of improvement matters a great deal to overall performance, and all avenues are explored. Where bicycles are exploring the benefits of marginally wider rims behind the tire, formula 1 teams explore ways to eject brake duct air upwards in order to put downward pressure on the tire to the ground.

Interestingly, cycling race strategy is very different from Formula 1, and I would argue this difference in strategy means that most, if not all, of the resources devoted to aerodynamic efficiency are essentially a waste. Cycling races are largely decided by who can do the least amount of work, and still cross the finish line first. While an aerodynamic bicycle certainly helps, body position, helmets, and the degree to which a rider can remain sheltered in the peloton determine the outcome. This is interesting, because it means that professional cycling is decided by team orders and strategy much more than the bicycle the rider is on, and yet manufacturers will consistently point to their equipment as the reason for an outcome.

You can’t sell effective team coaching, training, and smart riding in the peloton, and even where you can sell those things, Trek and Specialized aren’t in that business. They’re in the business of selling bicycles. To sell bicycles, one needs to produce a product that (1) looks aerodynamic to the consumer and (2) generates marginally better performance than a competitor, such that the difference can be advertised.

The 2023 Trek Madone landing page is a great example of this; the highlighted statistic is that the new Madone saves a rider 60 seconds an hour over it’s predecessor. Conveniently, they provide a white paper.

The first issue of note, is that half of the 60 seconds is due to Rider Position changes. Rider position changes can be achieved on the prior bike, and are not an improvement.

Second issue, the findings are at 45 km/h, 28 miles per hour. Air Resistance increases at the square of the speed increase. Doubling your speed creates not double the resistance, but closer to eight times the resistance. My typical riding speed is somewhere between 20 miles per hour, most of the time. Perhaps in a race, 25 miles per hour. By conducting testing at 28 instead of 20, they double the values they are likely to find due to the roughly doubled wind resistance compare to the recreational rider.

So just on those two things, it would be reasonable to say that of the 60 seconds of improvement in the Madone ’23, 30 seconds is rider position, and of the remaining 30 seconds, 15 is likely to be unrealized due to the speed at which the test is conducted. 15 seconds of improvement per hour. An hour is 3600 seconds, so .4% improvement, and just the frameset is $4,600.

I realize that this is a bit of a bummer, so to speak. It’s not fun to pour cold water on things that others have invested in (and anyone who purchases one of these bikes is invested to the tune of 5 figures, in the marketing claims of their bike). There aren’t independent or third party laboratories confirming results generated by the bike manufacturer making the claims. The whole space is awash in un-verifiable claims, backed up by the performance of athletes whose results depend on nutrition, consistent training, team dynamics, coaching, and luck. As riders, we’re exposed to an extraordinary amount of advertising that is intended to provoke the idea that “I need that in order to perform my best”. Resist that urge. You don’t need equipment, you need to be consistent, you need to plan your race, you need to practice your race efforts, understand your nutritional needs, to get an aerodynamic helmet and shoe covers, and do you best on race day. All this is (practically) free.