I would just like to add one more important point here. The correct way of pushing back the caliper pistons is to first loosen the bleeder screw, then push the pistons back with your tool of choice. Doing this requires much less effort and keeps any dirty fluid or deposits from flowing back into the resevoir and master. When doing this it is also a good idea to lubricate the caliper piston outer seals so they can smoothly retract into the housing.
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Teach a man to fish and he will never go hungry. Teach a man to rob a bank, he will never go fishing again.