As stated, you might have too much slack in your cable. Readjust (you have a tension adjust where the cable housing enters the caliper). As well, you have pad adjustment. See the red thumb dial ? That will adjust your inboard pad. I can't see, but you might also have an outboard pad adjustment for fine tuning. You can watch the pads / rotor gap as you adjust. Keep in mind, you want to make sure your caliper is centered/aligned properly before doing all this. The other thing you will want to do is clean your rotors / pad surfaces as well to avoid noise.
Last edited by clydeosaur; 04-17-14 at 04:12 AM.