Two years ago, my wife and I picked up a new tandem in Seattle and rode it home. Somewhere south of Portland my wife insisted we must have a brake rubbing. I thought she was just making excuses for how weak we had become. When the bike came to a stop while we were coasting downhill, I decided she may have a point. Unfortunately, the brakes on this bike require a 16 mm wrench to adjust, which I didn't have. Eventually I managed to get it adjusted, in the dark with two pieces of metal held as chopsticks, and our pace picked up considerably.