Aerodynamics is only for professional athletes? Far from it. Simple knowledge of aerodynamics increases the fun factor for all triathletes and cyclists. Here we give you some tips from a wind tunnel test with four team athletes (this article has been updated with current, sometimes surprising results in 2023).

In the summer of 2022, Team Riders Daniela Schwarz and Angel Hess were given the unique opportunity by Swiss Side to test their setting with the aerodynamicist par excellence, Jean-Paul Ballard (CEO of Swiss Side), in the wind tunnel at Airbus near Friedrichshafen. While Daniela tested with her triathlon bike and the appropriate equipment, Angel wanted to know with the normal road bike. The results were very revealing, for both.
Update: In early summer 2023, we were able to complete further tests, in the same wind tunnel with the same crew from Swiss Side. This time, Tempo Sport Managing Director Marcel Kamm was there with the triathlon/time trial bike and workshop employee Lorenzo Palandri with the road bike. These results are marked accordingly as a supplement included at the bottom of the text. They include other interesting material measurements such as aero calfs, the comparison of tri to time trial suits, aero helmets with goggles vs. visors, the effects of a wind gate in triathlon measurements, as well as the effects of helmets on road bikes and, above all, the effects of the new “fashion wave” of inward-facing hoods. You will be amazed by certain results!

Triathlon: Clothing more important than you thought

In Daniela’s case, adjustments to the seating position made it possible to save several watts. So far so good. Much more astonishing, however, were some other measurements. First and foremost, the choice of clothing. The switch from a sleeveless triathlon one-piece to the top model from Castelli with short sleeves brought savings of almost 20 watts. But another measurement was also interesting: It made practically no difference whether Daniela wore long (compression) or short socks or no socks, nor whether she rode with the water bottle (Xlab Torpedo) mounted on the handlebars or not. This is good news for all long-distance athletes who rely on exactly these pieces of equipment and thus do not suffer any disadvantage. On the other hand, the new Aerocalfs that appeared in 2023 have a positive effect. Details on this can be found in the update below.

Measurements Daniela 2022: There is a difference of about 30 watts between the worst (outlined in red) and the best setting (outlined in green). The triathlon suit alone accounts for 20 watts.

Update Summer 2023

In the new measurement with triathlon setting, the following (partly surprising) additional results were briefly summarized:
– The PR Suit (triathlon one-piece by Castelli, which also brought significant advantages in the measurement of Daniela) is even more aerodynamic than the long-sleeved time trial suit by Castelli (8 watts)
– The new Aerocalfs, which do not provide compression but are only worn for aerodynamic reasons (currently very trendy with many professionals), bring Marcel about 2 watts advantage (conventional compression scalfs a disadvantage of 2 watts). Aero shoe covers (the new ones from Castelli) bring 3 extra watts of savings.
– The aero helmet (“Mistral” by Kask) is always in the same wattage range with or without visor or with sunglasses. So it doesn’t matter if you ride with a visor or sunglasses. According to Swiss Side, this is also confirmed by many other measurements with other models.
– The head position is crucial: “Retracting” the head a little brings up to 17 watts advantage. So with a helmet like the Mistral, it’s worth keeping your head low as often as possible.
– Now the kicker, to a very rarely made but all the more exciting measurement: What makes wearing a (tight-fitting, light) Castelli wind vest at 45 km/h? Guess what! It doesn’t matter at all! It is a whole 2 watts slower with the wind vest. Even the experts were astonished, so the measurement was repeated several times, always with the same result. Possible explanation is that the material does not allow the wind to pass through at the front and thus gains aerodynamics, which are just compensated by the slight fluttering of the material. So the next time you compete in wet and cold conditions, you can confidently fall back on the wind vest (but it must be completely closed and snug!).

So dear hobby triathletes out there: If you want to save a lot of watts again, then pay special attention to your clothing, the head posture and as an optimization the aero calfs.

An upright posture on a racing bike is the purest brake parachute

What is the most aerodynamic riding position on a road bike? Our employee and team rider Angel tested it in 2022. Not surprisingly, the two positions “hands on top of the brake levers with low elbows” and the “simulated time trial position” (banned by the UCI in cycling races) are the two most aerodynamic positions. What is surprising, however, is the saving of watts. A whopping 112 watts (as well as 120 watts in the “time trial position”) can be saved compared to the handlebar position. Although the measurement was taken at 45 km/h, the savings should be significant even at lower speeds. And don’t forget: With headwinds or slightly sloping tracks, air resistance also becomes an issue for slower riders.

There is a difference of 120 watts between the best (green) and worst (red) position. Position 524.6, which is a little less radical, also saves 112 watts. Position 524.4 is significantly better than 524.3 due to the lower torso and bent elbows.

Update Summer 2023

In addition to various racing bike one-pieces, Lorenzo also tested the seating position. Here’s the bottom line:

– Fastest race one-piece (bike version) brings over 17 watts advantage over jersey/pants (Aerorace by Castelli)!
– Utopia aero helmet from Kask is almost 5 watts more efficient than Protone from Kask.
– Now the main finding: Inward-facing brake levers (hoods) bring an advantage of a good 11 watts thanks to a clear effect on the position of the upper body (inward-facing shoulders, lower head posture). So the pros, who have been riding almost all this way since this season, are right.
Conclusion summer 2023: With one-piece, aero helmet and adjusted position of the brake levers, you can easily get over 30 watts out of it. Not bad!

Conclusion: A streamlined position is extremely beneficial on the road bike. And all this without any financial investment. So on the next ride, pay attention to how you sit on the bike if you want to save some energy for some reason or if you want to move as quickly as possible in the headwind. In addition, it is worth checking the position with regard to brake levers: The new trend among the professionals of inward-facing hoods can save a lot of watts. But you must also be comfortable with this position! A one-piece suit and an aero road helmet such as the Kask Utopia bring further substantial advantages.

Conclusion

The triathletes (in competition) welcome any watt saving. In addition to the usual measures such as triathlon handlebars, balance bikes, helmet, clothing is also crucial. Also as an update: head posture and shoe covers/aerocalfs. Such savings are always interesting, whether you are ambitious or not. After all, who likes to waste energy (in competition) unnecessarily?

The Gümmeler fraction can save a lot of energy, especially through the seating position. This is not so important for many, as they simply drive for pleasure. But especially in a group, in a gruelling headwind or then in competition, it is certainly of great advantage to talk about the differences in the sitting position, the size of the seat. helmet as well as the orientation of the hoods. Above all, the realization that the wattage savings can be enormous opens the eyes of one or the other. To have or not to have an additional 100-150 watts (!) is the question here 😉