What Is a Crank Arm?
A crank arm is an essential component that facilitates pedaling on a bicycle.
Each bicycle has two crank arms attached to the bottom bracket at the bicycle’s center, integrated with pedals. These arms are crucial for transmitting force to rotate the pedals.
Constructed from materials like aluminum alloy or carbon fiber, crank arms are designed to be both lightweight and durable. In competitive road cycling, the preference leans towards crank arms that are not only light but also stiff, optimizing performance. The length of a crank arm plays a significant role in matching a rider’s height and physique, as well as in maximizing pedaling efficiency. While longer crank arms can increase torque, potentially causing muscle fatigue, shorter crank arms tend to support smoother rotation and better pedaling efficiency.