When pads and rotors are new, they have to be “bed in” before they reach their full braking potential. This is achieved by first accelerating the bike to a moderate speed and then firmly applying the brakes until you are at walking speed. Repeat this process 20 times. Then accelerate the bike to a faster speed and apply the brakes until you are at walking speed. Repeat this process ten times. It’s important that during this process you never come to a complete stop or lock up the wheels at any point. The idea behind bedding in a brake is to evenly distribute pad material across the rotor to improve the coefficient of friction between the two components. Coming to a complete stop causes a build up of pad material in one spot that can lead to pulsing and noisy brakes.