Just built a new road bike with Shimano 105 BR-R5800 brake calipers. After the first ride I've noticed that the front arm has become loose and has play (about 1mm) if you rock it back and forth. I've circled the loose pivot in the photo below. I tried tightening the bolt as you would on the older style brakes but it seemed to be fully tightened up and adjusted correctly. Is it normal for this model to have a bit of play?