lamboluver

I recently got a bike with hydraulic disc brakes (Shimano M455 Calipers). I notice when I squeeze down the levers and move the bike back a forth the pads actually move inside the calipers. I normally would not think of this as a big deal but I think it might be causing a noise every time I hit the brakes. Is this normal with hydraulic disc brakes? And if not could this noise be coming from something else? It is usually a tapping/ clicking sound as soon as the pads make contact with the rotor.

Thanks for the help.

reptilezs

also check wheel bearings and headset

DMF 

Disc brake pads are not fixed to the piston/caliper like 'armature' pads. When applied - squeezed against the rotor - the pads are pushed against a retainer/keeper that keeps them from sliding out from under the piston. Movement is normal. Such movement is not the cause of noise. A clicking sound could be interference or an irregularity in the rotor.

DMF 

Yes. And spokes. Disc brakes apply stresses to the wheel assembly and fork that rim brakes don't.