Olsson and Brothers MARATHON Guide De L'utilisateur Et Garantie page 23

2. Turning the adjustment 2 brings
the piece 4 closer to the disc. This
adjustment can be done with the Allen
key provided with the equipment.
3. The adjustment must be as shown in the bottom photo.
4. To check that the pieces do not stick to the disc, lift the rear wheel and turn it by
hand. If it turns freely and there is no friction, the adjustment is correct. If any friction
or braking is detected we will have to reverse the initial adjustments until these frictions
are corrected.