Perhaps the best description of single speed mountain biking is this ­ “Always the wrong gear.” While singlespeeding is a challenge, there is no question in its rise to popularity in recent times. Maybe you don’t always want a couple dozen gears and gobs of travel out on your favorite rides. And maybe sometimes the challenge is the best part of the ride. But no matter the motivation to take on the test of that single wrong gear, you can always have the right hub.