There is a lot of drag on my front rotors. I cannot spin the rotors by hand more than about a half turn. I believe the wheel bearings are good. It looks like the caliber pistons don't retract enough. How much should they retract? How much of a gap between the pads and rotors should there be? I flush the brake fluid once a year. The car is driven about 30 miles twice a week, mostly city. All calibers rebuilt about 15 years ago and master cylinder replaced.