12 Drive Train Design

The human rider provides the power. The drive wheels develop the force to push the vehicle forward. In between is the drive train—the set of components that transmit power from human to wheels. While many aspects of a vehicle affect performance, comfort, and effectiveness, few do so as much as the drive train. Cadence, force, and stroke must be set correctly to prevent fatigue, discomfort, and even injury. However, the torque and speed of the drive wheels generally differs substantially from the optimal values for the rider, described in Chapter 5. Good drive train design bridges this gap, and does so with very little loss of energy.