Recently I have experienced a clicking sound from direction around the engine,
the gear shifting was somewhat worse than before.
It turned out the rear wheel rubber damper needs a change.
Until the new ones arrived I implemented some bicycle inner tube segments.
At first in 1mm thicknes around the hub segments, it needed more so installed 2mm thick ones on the walls.
The hard clicking sound gone but not all, the gear shift became more precise as it was before.
Should be added I rarely use the clutch for shifting gears.
The hub still moving a bit, so that kind of cure isn't a full repair,
but temporarily it's ok.
For installing the new ones I have covered the rubber in some talcum.
The rear hub and the chain sprocket not in perfect line with the wheel, the sprocket has some 0,50 - 0,70 mm swing from left to right (don't know what is the exact english expression for this),
with the bicycle tube segments it was around 0,2mm,
so the wheel must be out again.
(some say it not worth the word, but for the automatic chain oiler the plain run of the sprocket has some significance.)
Here comes some pictures:
