Originally Posted by Niles H.
I don't have the numbers with me (maybe someone else knows them, or knows where they can be found?), but higher and higher percentages of a cyclist's energy go into overcoming air resistance as speeds increase. I've seen charts for this, and it is dramatic. Especially at higher speeds, the limiting factor -- and the factor that is really slowing you down -- is air.
I have read this too. Friction, which is where weight comes into effect, is a linear function. Air resistance is a cube function of the air speed. Apparently cyclists should be more concerned about aerodynamics than weight, especially if you ride in the wind a lot like I do.