The overwhelming majority of my miles anymore come on my 11 mile each way commute. (No, I don't care how fredly that is.) I ride half the time on my loaded down cross bike, and half the time "light" on my Cannondale CAAD9. Somedays I push hard, other days I pedal easy.

And for some reason, no matter which variable changes...either the bike or the effort...the average works out to about 16mph. Weird.

I can hit a sprint on the home stretch of 35mph, or I can spend the entire ride just spinning and chatting, and it still works out that way. Must be some strange space-time continuum disruption I pass through.