How does a manual choke work?

A manual choke works by restricting the airflow into the engine's carburetor, enriching the fuel-air mixture to facilitate cold starting. When the choke is engaged, a valve closes, reducing the intake of air and allowing more fuel to enter the combustion chamber. This richer mixture helps the engine start more easily in cold conditions. Once the engine warms up, the choke can be manually disengaged to restore normal airflow.