Originally Posted by chuckywang
That Stoptech article says that vibrations during braking are not caused by warping. Instead, it gives the reason as "friction pad material transferred unevenly to the surface of the disc". My question now becomes: What caues the friction pad material to transfer unevenly to the surface of the disc? I couldn't find the answer to that anywhere.
Another question I had regarding that article is this: Does the article imply that warping (ie misshapen rotors due to excessive heat) doesn't exist, or does it imply that it exists, but it just doesn't cause vibrations during braking.
Do a google search on "rotor runout" that's what gives you the pulsation in the pedal. Rotors don't actually warp, it's when the rotor wobbles past it's maximum tolerance (measured in thousandths of an inch) and the pad will actually wear low spots in the rotor causing the "warped" rotor feel.