I am about to replace my brake pads front and rear. My rotors are not bad looking they have no groves or anything like that. I didn't know if they could or should be turned or sanded down or scuffed with sand paper or what? The reason I am replacing them is because they kinda squeal a little when I brake both front and rear and I don't know because I just bought my bike used but I think they are the original pads. I saw toyo or something like that on the back on one of the front pads.