Motorcycle brakes are like automobile brakes. When you spin the wheel does it make an uneven sound like a warped disc or is it a constant sound like a sticky caliper. They will always touch the rotor when not being used, but if you can feel that one side is sticking then you should have the calipers rebuilt/replaced. I would also check the brake lines to see if they are bad. Squeeze the brake lever and check the lines for bulging.
'00 Katana 600
39 speeding tickets and now I have a V1.
87 days till freedom