Heinz, I would suspect the UJ's on the steering shaft, mine look a bit basic quality & I suspect are not OE tested for alignment
As you know if you rotate a single knuckle UJ with the shafts at an angle you will get a spike in rotational resistance at the peak of 'kink', I once had an advisory on an MOT for a previous Mog for play in the steering UJ's (but turned out to be the bulkhead thrust bearing mount)
