Had this on my 916 & 996, angular contact ball bearings give very nice feeling to the steering but are very sensitive to the load unlike the taper roller bearings used in most jap bikes (had same problem on R1 which used same type of ball bearings).
Just get the tool or make one (you dont need to engage all the holes, I made one from a nut & drilled 4 holes & fitted dowl rod worked fine for me) and adjust the bearings when you feel the front moving or making a noise.
You need to be really careful with these ball bearings you should not over tighten them as this could mark the races.