· found my old avatar
I'm going to bet that the reason there is no return spring on a hydraulic disc brake system is to allow fast, positive brake response. You don't actually get a lot of movement of the brake pads when you push on the hydraulic fluid with the small piston in the master cylinder, and I would think there is no real pad travel to spare. My bike was up on the lift yesterday and you can definitely hear and feel the drag, but since they don't heat up, I doubt it amounts to much. Just a thought.