Jersey Aerodynamics

Posted on Posted in Rouler ELITE Jerseys

The energy saved and time gained from wearing a jersey that fits better – even the same jersey in one size smaller – was more significant than buying faster wheels worth thousands of Euro.

The major bike manufacturer Specialized has carried out some wind tunnel testing comparing the time gained and energy saved by a rider who wears a loose jersey and one who wears a tighter, or fitted jersey.

The results apply to everyone; whether you’re a top domestic racer, a sportive rider or somebody who cycles simply for some exercise and has no goals beyond that.

The data thrown up by the testing featured in the video below shows that selecting a fitted jersey over a regular shaped one can be very significant.

This is especially so over a long ride. Even opting for a smaller size when you buy a jersey can make a considerable difference in terms of what you get for the effort you put in.

Irish rider Philip Deignan, who races with Team Sky, revealed in his stickybottle diary during the Giro d’Italia that his skinsuit – that’s a one-piece tight fitted jersey and shorts – was so tight and was fitted to the riders’ time trial position to such an extent that he had to be helped into it and could not stand up straight in it off the bike.

The Results

Testing a rider wearing a fitted, versus looser winter top was worth 83 seconds over 40km. That’s more than 5½ minutes over 100 miles.

And if you are riding in a group, while the time saving is irrelevant because you will clock the time of the group; you save the energy that it would take you to ride the same course 5½ minutes faster.

In other words, if everyone in the group switched from regular or baggy winter jerseys into fitted or smaller ones, the group would complete a 100 mile ride 5½ minutes faster.

And when it came to a short sleeve jersey that you’d wear in warmer weather, the difference between a fitted and baggier jersey was 91 seconds per 40km.

That saving was made by not only wearing a more fitted jersey, but also by choosing a smaller size. So the test basically involved a medium size regular, or ‘club fit’, jersey against a size small fitted jersey.

That section of the testing was interesting because it means even if you are not going to go out and spend extra money on fitted racing-style kit, you should be at least thinking in terms of buying the smallest jersey possible, while also taking comfort and look into account of course.

Simply choosing a smaller sized jersey is worth several minutes over a long sportive or training ride, according to this wind tunnel research.

And if you are riding in a group, while you will not save that time, you will save the energy that it would take you to cover the course several minutes faster. It’s not to be sneezed at.