Which component atomizes the fuel at low speeds?

The main jet is crucial for atomizing fuel at low speeds because it controls the amount of fuel that is mixed with air before entering the engine. At lower engine speeds, the airflow through the carburetor is less forceful, which makes it essential for the main jet to ensure that the fuel is broken down into fine droplets to create a combustible mixture. This atomization process is vital for efficient combustion, especially during low-speed operation where the demand for fuel is lower and where an adequate air-fuel mixture must be supplied to initiate proper engine performance.

In contrast, while components like the choke valve can enrich the mixture for starting, and the throttle valve controls airflow to the engine, these do not directly play a role in atomizing the fuel. The slow air bleed contributes to fuel atomization but is not the primary component responsible for that process at low speeds.