Hubster I did front brakes this afternoon on my '16 ZX-10R and ran into a bit of a snag. These are the OEM Brembo M50 Monobloc calipers that came standard on that year ZX-10R.
Anyway, I deglazed the rotors and spit polished the caliper pistons before fitting the new OEM Brembo pads. Got her all done and gave it the Armstrong test and it turned about three times, very quiet except for a metallic metal on metal sound each time a certain spot on the left rotor passed the caliper.
I removed the left caliper and no sound. Took the caliper apart and rechecked everything and it all looked good so reinstalled the caliper and the noise was still there.
Using a flashlight and mirror I checked for any metal to metal contact between caliper and rotor, none found.
Removed the caliper again and pushed the pads back ever so slightly and
retorqued the caliper bolts and spun the wheel, no sound this time.
So I had now confirmed the problem was in the rotor to pad contact.
I was now running out of daylight so buttoned it back up and did a garage floor push test of the bike and it was smooth as a baby's bottom, no noticeable sound or brake drag, dead quiet.
My best guess is there may be an ever so slight warp in the left rotor or a slight defect in the rotor surface that is grabbing the pad.
Your thoughts Oh Master Of All Things Brembo... 
