How does the rear wheel rachet of bicycle look?

The rear wheel ratchet of a bicycle is a crucial part of the drivetrain that allows the cyclist to pedal forward while preventing the bike from rolling backward. It is typically located in the rear hub and consists of several components:

1. Ratchet Ring: The ratchet ring is a circular metal disc with a series of evenly spaced teeth or notches cut into its circumference. It is securely attached to the rear hub shell.

2. Pawls: Pawls are small, spring-loaded arms that engage with the teeth of the ratchet ring. They are usually made of durable metal and positioned around the hub's inner diameter, facing the ratchet ring.

3. Pawl Springs: Each pawl is held in place by its spring, which keeps it in contact with the ratchet ring.

Operation:

As the cyclist pedals forward, the pawls engage with the teeth of the ratchet ring, preventing it from rotating backward. This allows the wheel to rotate forward, propelling the bike. When the cyclist stops pedaling or pedals in reverse, the pawls disengage, allowing the wheel to rotate freely backward without driving the drivetrain.

The design of the rear wheel ratchet ensures that the bike can only move forward when pedaled and prevents unwanted backward motion. It is a critical component that contributes to the functionality and safety of a bicycle.