There are lots of articles on the internet about how much faster you climb on a lighter bike. The answer is pretty much: a lot less than most cyclists think. And not enough to account for the difference between us Sunday or at Greylock. Here's an
example. Indeed, I gained more time from losing five pounds over the summer than the gain I get from a lighter bike. But, of course, seconds matter when you're competing (with me :-) ), and not just biking for exercise.