Originally Posted by FBinNY

The two little screws above the pivots, are to balance the springs. You tighten them to raise the spring tension to move the close arm out. Conversely,you lower the tension on the far arm to bring it in. Generally you'd do some of both, rather than take one screw to the extreme.

Also check that the cable is truly free, especially for the rear brake. Often a cable cut a bit too long or too short pushes or pulls on the arm making balancing difficult. Lastly make sure to put a drop of light oil on each pivot before adjusting the springs. Pivot friction can make a decent job impossible, so oil first, adjust later.