Bedding In New Pads and Rotors

New pads grab oddly, or the brake squeals from the first ride. That's common, and often it means the brake hasn't been bedded in yet.

What bedding in means

SRAM defines bed-in as controlled slowing. The braking surface heats up gradually, and pad material is spread evenly onto the rotors.¹ In other words, you brake in a planned way so a thin film of pad material settles onto the rotor. SRAM says that friction between the two surfaces enables powerful braking.¹ iFixit describes it in similar terms. A super thin layer of pad material gets distributed onto the rotor.²

Why makers ask for it

SRAM says doing it properly gives consistent performance and minimal noise.¹ It calls bed-in critical for new brake systems, pads and rotors, and says its own steps take about 10 minutes.¹ iFixit adds that a new bike may need it to avoid squeaking from new discs.²

Pad type changes how much work it is. According to SRAM, sintered pads require a more thorough bedding-in process, while organic pads need less time.¹ You can read more in pad types.

When you'd do it

Think of the moments when the pad and rotor surfaces start out fresh and untried:

• A new bike.
• New pads on an old rotor.
• A new rotor.
• A change from one pad type to another, which SRAM says calls for new rotors too.¹

The steps themselves

This page doesn't print a step-by-step routine, on purpose. SRAM says to use its specific steps for its brakes.¹ Other makers have their own. Look in the manual that came with your brake, or on the maker's support site for your model. Search for the brake's name and the words "bed-in procedure", and use the maker's own page, not a shop's blog.

This site doesn't give riding or road-safety instructions. Follow the maker's written steps for your brake, and your local road rules.

After the bed-in

Keep the braking surfaces clean. SRAM says skin oil can contaminate a pad and reduce braking performance.¹ Park Tool's rotor guide ends a fitting with an isopropyl alcohol wipe.³ Check your own maker's cleaning advice first, though.

Still squealing, or still weak? Don't assume the bed-in failed. Alignment, contamination and worn parts can cause the same symptoms. Go back to worn pads and work through the causes in order.

Pad and rotor must suit each other

SRAM also warns that a fresh compound on an old rotor may bring noise and weaker braking.¹ SRAM's answer to a change of pad type is to replace the rotors as well. Pad types has the details.