The bike has been a bit noisy and rattly during the last months, and the rear brake wasn't operating properly.

Let's get started!

The bearings and the brake shoes do not look damaged, but the grease is cooked.

I'm always impressed how the managed to fit 5 gears in such a small package.
Exept the cooked grease, there's not much play and it's possible to get rid of the old grease with gas or brake cleaner (you'll probably notice plenty of tiny metal particles in the grease).

Now it's all clean, so let's start the puzzle.
I used 10W40/5W40 engine oil for the inner bearings and the gears, MoS2 bearing grease for the external bearings and the brakes(specific grease should be used for the brakes).

Ready to ride!
Shifts smoothly, operates and brakes quietly.

Vielen Dank, Herrn Fichtel und Sachs.