Situation - inconsistent engine temperature.
When I bought my (new to me) 2018 R1200 GS TE in May 2019 it had a total of 1,400 miles on clock. Despite the ambient temperature, riding conditions, engine load and speed the temperature gauge repeatedly moved between the range of 82 to 96. When it reached 96 it would then rapidly drop down to 82 then slowly climb to 96 and repeat the sequence.
Investigation.
When I went touring from May 26th to June 10th 2019 I rode in Spain, France, Switzerland and Belgium; the ambient temperature ranged between 9 to 35 degrees centigrade. Again the engine temperature gauge repeatedly moved in the same sequence; again irrespective of how it was ridden nor the engine load.
Resolution.
I've booked the ferries for another tour of Spain & Portugal in Sep' & Oct' 2019 and three weeks ago I fitted some more expensive Farkles, including some (inexpensive £35.00) O.E.M. BMW radiator guards. It may be a coincidence, however after fitting the rad' guards, the temperature gauge NOW consistently displays 82 (however, it sometimes VERY momentarily displays 83 then immediately drops down to 82); this is irrespective of how it was ridden nor the ambient temperature.
Root Cause.
The bike is like a lady and was not happy until adorned with yet further additional expensive Farkles.