Why do disc brake systems generally not require adjustment?

Disc brake systems generally do not require adjustment primarily because they are designed with self-adjusting mechanisms. As the brake pads wear down due to use, the design of the system allows for the calipers to automatically compensate for this wear. This automatic adjustment maintains the proper distance between the brake pads and the rotor, ensuring consistent braking performance without the need for manual intervention.

Self-adjusting mechanisms in disc brake systems work by utilizing the hydraulic pressure and the motion of the calipers to close the gap created by pad wear. This means that as the brake pads become thinner, the caliper moves closer to the rotor, keeping the effectiveness of the braking system intact.

In contrast, drum brake systems typically require manual adjustments because the shoes do not move as readily in relation to the drum as pads do with the rotor in disc brakes. While the other options address various characteristics of brake systems, they do not directly pertain to the self-adjusting nature that is pivotal for disc brakes.