What are the two types of disc brakes?

• A. Hydraulic and Magnetic brakes
• B. Mechanical brakes and Hydraulic brakes
• C. Mechanical and Electronic brakes
• D. Cable and Hydraulic brakes

Answer: (B)

Disc brakes on bikes are driven by two main actuation methods: hydraulic and mechanical. Hydraulic brakes use incompressible fluid in sealed lines; when you squeeze the lever, fluid pressure pushes caliper pistons to clamp the pads onto the rotor, giving strong, smooth, and highly modulated braking with relatively little lever effort. Mechanical brakes use a cable from the lever to the caliper; pulling the lever tensions the cable to move the caliper and press the pads against the rotor. This setup is typically simpler and cheaper but can require more lever force and be more affected by cable stretch or contamination, leading to less consistent feel.

Magnetic brakes aren’t a standard bicycle disc brake system, and while electronic braking exists on some bikes, the common, widely recognized disc brake types are hydraulic and mechanical. The term “mechanical” corresponds to cable-actuated brakes, which is why the correct pairing is mechanical and hydraulic.