Bought a second hand Yeti Arc recently with these brakes fitted. It's not had a lot of miles on the bike since build apparently, perhaps 300 mostly commuting with 1 decent MTB ride. Both front and back brakes catch slightly on the disc. From the manuals, research and YouTube it would seem that adjusting these should be an absolute doddle. Loosen the top and bottom hex bolts, squeeze brake, tighten. Still catching, not a lot but enough to slow the wheel down if I spin it. These are my first hydraulic disc brakes so I'm reluctant to do too much without making sure I get all the help I can. I'm thinking maybe one of the pistons isn't returning properly. Perhaps the spring clip is weak ? Perhaps I need to take out the pads, carefully push back the pistons, clean down with rubbing alcohol ? All hints, tips and advice much appreciated.