Just swapped a new pair of disc brake pads?
Before you head out for your first ride on the new pads and expect plenty of braking power, you’ll need to bed them in first.
Bed-in is a straightforward procedure that many cyclists often overlook. Many would then complain and wonder why the braking power is still bad even with new brake pads.
What is brake pads bed in?
Bed-in is a process of transferring the brake pad materials to the disc rotor using kinetic-to-thermal energy transfer.
When the brake pads heat up through adhesive friction, the brake pad materials are deposited onto the rotors, thus giving the brake pads something to grab on.
The bedding process also sculpts the brake pads and rotor’s surface to mirror each other to maximize the contact surface area.
Why you should bed in your disc brake pads
The first thing you’ll need to do after replacing the brake pads is to bed them in so that they can perform at their full potential throughout their lifespan.
Bedding in your brake pads increases braking power and prevents the irritating brake squealing sound often associated with disc brakes.
How to bed in your new brake pads
Bed in your brake pads immediately after swapping a new one. It only takes around 10 minutes to finish the process.
Here are five steps to bed in your new brake pads.
- Find an empty road with a slight downhill gradient (3 to 5% is ideal). Slowly ride up to the crest if you’re at the bottom.
- Descend at a moderate speed, around 12 to 20mph (20 to 30kph).
- Start with the front, and gently apply the brakes with even pressure. Let the brake pads and rotor rub onto each other for around 15 seconds. Do not brake hard to a complete stop.
- Repeat 10 times. You’ll hear squealing sounds for the first few repetitions. Eventually, you’ll start to feel that the braking power gradually increases with each repetition.
- Repeat Steps 3 and 4 for the rear brake.
What the manufacturers recommend
Looking deeper into each brake pad manufacturer’s recommendations, there are slight differences, especially regarding brake pad and rotor design and materials.
The steps I laid out above are what’s generally done by the majority of cyclists. While the number of repeats and timing might differ, the general principle is the same.
Shimano recommends applying uniform pressure to the front brake at 12 to 15 mph (19 to 24kph) to a walking speed and repeating for 15 to 20 times.
Then repeat the same procedure for the rear brake.
SRAM recommends applying firm pressure on both brakes to slow down the bike from a moderate to walking speed. Repeat the process 20 times.
Then, repeat the same procedure above but starting at a faster speed.
Swissstop recommends dragging each brake for 20 to 30 seconds on a slight downhill, alternating between front and rear. Repeat three times.
Then, repeat the same procedure but on a steeper downhill.
TRP recommends a longer bed in the process for their metallic brake pads.
Get the bike up to around 15mph (24kph) and use the front brake to slow down to 5mph (8kph). Repeat 20 to 25 times. Once done, repeat the same process for the rear.
Magura recommends getting the bike up to around 18mph (30kph) and dragging the front brake to a standstill. Repeat at least 30 times. Once done, repeat the same process for the rear.