Are you talking about nut #4 ?
If it's the case, the stud is probably turning in the rubber bumper. They are replaceable separately (parts #50)
BMW VIBRATION DAMPER Part # 11117682158
THIS ITEM FITS:
2012 BMW R1200GS
If it's the case, the stud is probably turning in the rubber bumper. They are replaceable separately (parts #50)
BMW VIBRATION DAMPER Part # 11117682158
THIS ITEM FITS:
2012 BMW R1200GS