So - its time for the forks to get serviced.
I only have 8900km on the forks after service.
And the oil is filth. The valves are almost jammed and there is so much overheating going on in the forks. The rebound adjuster was stuck and the aluminium tube was full of burnt oil. Why so fast???
Suppose the oil chosen was too thick for our side of the weather. It is mainly cold here - and the 5w oil does not do its work properly.
I will try the motorex 2.5W as next and adjust the forks to stock.
The oil level will be set to 120mm as suggested by the WP and hall of wisdom.
Then - weŽll see in the springtime, how stuff works in the rough stuff and under more load and travel weight.
Here 2 pics of the "damage".