Per Otis, I measured from center of mounting bolt to midway of the pad slot, when the calipers are slightly closed. What I had on there was about 5cm. I have a few more sets about the same, so I might guess these are typical short reach. Are there very short reach calipers out there?

And, I have to ask a totally naive question: what are "nutted style" brakes? There is a nut on the backside of the mounting bolt; does that make them nutted? On newer bikes there is another connection method? I have never really touched a bike that was less than 20 years old.

jim