Depending on the manufacturer, anywhere from .001" to .006".
worn thin
A disc brake rotor with excessive run out is a warped rotor which causes a pulsation in the brake pedal when the brakes are applied. A certain amount of run out is acceptable.
disc brake components
The rotor is the disc in the disc brake system.
Disc brake rotor? A pulsation in the brake pedal when applied. Distributor ignition rotor? The engine may not run or run poorly with misfires.
A symptom of excessive brake disc run-out is a pulsating or vibration felt in the brake pedal when braking. This can occur due to uneven wear or warping of the brake discs, leading to inconsistent contact with the brake pads. Additionally, drivers may notice a squeaking or grinding noise during braking, indicating a potential issue with the braking system.
In case of cost..drum brake is better than disc brake.
Converting a rim brake wheel to a disc brake system involves replacing the wheel hub with a disc brake-compatible hub, installing a disc brake rotor, and attaching a disc brake caliper to the frame or fork. This process may require specific tools and expertise, so it is recommended to consult a professional bike mechanic for assistance.
There are many purposes to using a disc brake. Disc brakes are mainly used in industrial drills because the disc brake stops the drill gently so it doesn't overheat.
The disc brake caliper is attached to the steering knuckle or spindle.
Disc brake pads and drum brake shoes
pad brakes are disc brakes, it's known as changing brake pads for disc setup and changing brake shoes with drum brake setup.