Started by the Pedalwise team from official manuals, support pages and repair videos

Disc brake pads are the friction blocks inside a disc brake caliper that squeeze the rotor.

What it's used for

Park Tool says to replace pads when they are worn, when they are contaminated, or when you want a different pad material (Park Tool pad guide). It gives a minimum of 1 mm of pad material, roughly three stacked business cards, and says to check the maker's own wear spec (Park Tool).

What to look for

• The exact pad for your caliper. Look up your caliper model on its maker's site, or bring the old pad to a shop. A pad of the same shape will usually fit (Park Tool).
• A compound that suits your riding. Park Tool describes organic, semi-metallic and metallic pads, each trading off noise, initial bite, rotor life and pad life in wet and dry conditions (Park Tool).
• Rotor compatibility. Some pad and rotor combinations don't work together, so check the markings on the rotor and the pad packaging (Park Tool).

Using it safely

• Keep oil, grease and brake fluid off pads. Park Tool notes contamination is often hard to see and shows as squealing, extra lever effort, or a dark surface that smears (Park Tool).
• Note how springs and clips sit before removal, and reinstall retaining pins and clips fully (Park Tool).
• New pads need bedding in before hard use. See Bed in disc brakes.

Guides that use it

• Replace disc brake pads
• Bed in disc brakes
• Adjust mechanical disc brakes
• Bleed hydraulic disc brakes

Sources

• Disc brake pad removal and installation, Park Tool