Im using shimano floating rotors, newish ones. Yes you have to pump the brakes a bit at first so the pistons move closer to the rotor but even once the pistons are pushed closer to the disc there seems to be quite a bit of lever movement before they bite. Are they supposed to be like this? Chap in bike shop said to change the reach on the lever so they are further from the bars but i can obviously only move them so far away whilst still being able to reach them!