Originally Posted by
donrhummy
It can make a difference but most of the benefits are not seen until you're traveling at a high speed (23-25mph+).
2. Aerodynamic drag increases exponentially. For example, going 20mph takes 239 watts while 15mph requires 110 watts (for the default rider stats seen here:
http://kreuzotter.de/english/espeed.htm). That's 129 extra watts to increase 5 mph. But increasing another 5mph to 25mph, requires
446 watts (again for that "default" rider). That's 207 extra watts! So a more aero frame will make a greater advantage at higher speeds.
The interesting thing is that whilst the above is true, because the slower ride spends more time on the course he/she will save more absolute (as opposed to relative) time from the aerodynamics than the faster rider, despite travelling slower... take the overshoe example; a rider travelling at 17.5miles in an hour saves 33 seconds, whilst a rider travelling the same 17.5 miles in 45 minutes saves just 27 seconds.... the same effect can be seen with riding on the drops... a more aero bike, etc....
Don't take my word for it.... the nice guys at Cervelo have written a nice page on the effect here:
http://www.cervelo.com/en/engineerin...st-riders.html