Many of us are converting frames designed for older 27" wheels to use modern 700c wheels. A common problem is brake reach - such that when you swap in the smaller wheels, your brake calipers don't reach quite far enough. Most modern brake assemblies a) are very short reach and b) use recessed nuts for mounting.

On older frames, you basically have two options (as I understand it).
1) Find older nutted long-reach brakes that fit (by nutted brakes, I mean brakes that have the full length bolt that reaches all the way through the fork, etc, allowing you to use a standard nut). This is an increasingly difficult option.

2) Find long reach recessed brakes and drill out the back of your fork, etc to accept the recessed nut.

Well, I didn't want to go with #2, so I began the search for long-reach nutted brakes. I'm also sick of messing with centerpulls (coming from mafac racers), so I wanted a dual-pivot caliper design. I originally picked up the Tektro 800a for $18 (http://www.modernbike.com/itemgroup.asp?IGPK=2126175524). However, I wasn't thrilled with the quality and didn't like that they lacked the "quick release lever" for the brake cable. So, I also picked up a pair of the Tektro R556 calipers for $45 (http://aebike.com/page.cfm?action=de...=30&SKU=BR7303). As it turns out, the bolts are interchangeable! After a little work disassembling the calipers, I'm left with a NUTTED R556 set and a recessed 800a set!

Awesome. I've mounted the Nutted R556's on my bike and they look great - definitely a nicer brake than the 800a's. Of course, if you're just looking for the cheapest possible solution, the 800a's might be sufficient by themselves. Anyway - just wanted to share my findings and hopefully save the next guy the hassle.