The only wear part during the first 50'000km may be the left industrial bearing.

- For changing this bearing, first dismount the Schlumpf drive (-> I.14.)
- Hold the right crankarm in a vice according to photo on the right.
- Unscrew the self locking nut.
- Lift off the bearing.
- Count the number of shims, that were positioned between circlip and bearing.
- Put the same number of shims between circlip and new bearing.
- Set the new bearing.
- Adjust gearing play and install the drive again.