What kind of brakes?
Good brakes are essential. Many tandems are now fitted with linear pull (v-brakes). When combined with an appropriate brake lever, these brakes are very good on a tandem. I don’t actually like v-brakes on a single, because it is so easy to do an endo with them, but tandems don’t have that problem. The problem is that lots of folks want integrated brake-shift levers and these are not designed to work with linear pull brakes, so some adapter has to be used that ultimately compromises the advantage of the linear pull lever. Lots of folks will tell you that they work fine, but they could be better. We use bar end shifters, so we can use properly mated levers and brakes. Bar end shifters are also handy for telling what gear you are in. Unlike a single, the captain can’t just look down to see. One of our bikes does have v-brakes, mated with DiaCompe 287 v-levers designed for this purpose. It works quite well. The road bike uses Ultegra caliper brakes, and they are fabulous. Our touring bike