There should be a very small allen key stud in one of the break calipers you use this to level out the tension on the calipers. ie , lets say the left caliper has the adjuster on it and the right caliper is sticking to the wheel, in this case you would release the tensioner on the left caliper by screwing it out (anticlockwise) if the left caliper was sticking you would screw the tensioner in (clockwise) it should be a approx 3mm allen key to do this (check first) have a look around the break calipers , you should see it. if you dont know they are there you dont easily see them . good luck.
Martin
May 2009