On the Wheel
 

Whenever there is a breakaway taking place the riders chase after him and Phil says, "he's on his wheel". Now I know about the slipstream and the advantage you get riding behind someone else, but does riding on someone's wheel actually slow them down?

I'm thinking that when the breakaway gets caught then he stops pedaling harder and slows down because there is no use in expending more energy rather than catching the wheel actually causing him to slow down.

I saw a report quoted recently that found that when someone rides hard on another's wheel (within a few poofteenths of a mm), the rider in front gains about a 2% advantage (reduction in effort) due to better air flow. The big advantage is for the rider behind which is in the order of 30%.

Richard