Most recreational cyclists don't give aerodynamics much thought. Sure, we 're all used to seeing our favorites in the Tour de France time trials looking like beings from the future with their skin suits, teardrop aerodynamic helmets and super sleek bicycles. But is all that geeky science of speed stuff only for the professionals?
Well, if you have ever had to battle a headwind on a day when you just didn't need anymore difficulties, you know that aerodynamics affect everyone, not just those with a pro contract.
With that being said, there are differing levels of concern from your recreational cyclists to your pro tour professional. The Tour riders look at the most minute details of everything, from bike design to the wind drag from a pair of sunglasses. While on the other hand recreational cyclists don't need to drill down to that same level of minutia. There are however some easy and obvious things one can do to become more efficient at avoiding the wind, and it might help make you faster.
Clothing and Body Position
First off, flappy wind jackets, especially those which billow like a sail as one moves forward are to be avoided. If a jacket must be worn, find one that is form fitting and reduces the amount of extra material. In fact, all flappy clothing is an aerodynamic nightmare. Form fit if you want to be fast.
The more upright you sit the more comfortable you'll tend to be, but that's not very "aero" so to speak. With today's more accommodating frame designs (including longer head tubes) using the lower position on the handlebars, or getting in the drops as it is called, is much easier than before. At moderate to high speeds I find that getting in the drops gives me about 1/2-mile an hour more speed for the same amount of effort.
The data and suggestions I am making are just my observations. Clearly, if you want to do real, scientific testing, the only way to go about it is by using a wind tunnel. Up until recently, there really weren't a lot cycling specific wind tunnels in the United States. For those wishing to do this type of testing, athletes had to use facilities designed to do aerodynamic testing for rockets, airplanes or automobiles, all forms of transportation which go much faster than a bicycle (especially when I am riding one).