brake reach, pad position and optimum braking power
I've been wondering lately about how reach & pad position relate to braking power, and wondering if someone could fill me in on how this works, and what's optimum for the best possible performance. It probably doesn't make a huge difference, but I'm curious - and it's a bit of a technical question, so I thought I'd take it to the mechanics.
To give a concrete context, my new setup (involving a number of new parts on a 1985 Nishiki Prestige) includes a set of mid-reach (47-57mm) brakes, Shimano B650(?)s; I was told that the old Suntour Cyclone calipers that came off the frame and forks I started out with ran 47-57mm, so that's what I got. Turns out that short reach would have worked...better. With 700c rims, the mid-reach brakes need the pads to be set up right at the very top of the slots, and the little bolt on top slightly relaxed (these are new dual-pivot brakes), to get a good position. Obviously, 39-49mm brakes would be down near, but not quite at the lower end of the slots. I feel like that would give more leverage, and thus closer to optimum braking performance. Does this make sense?
Down the line, if I can find a use for the mid-reach calipers elsewhere, would it be worth my while to swap them out for short-reach? If anyone is particularly knowledgeable, I'm kind of interested in the physics/mechanics of this as well as the practical side...