Pratissoli KSR Serie Manuel D'utilisation Et D'entretien page 41

9.11 Transmission definition
To prevent irregular radial loads on the shaft and the relative
bearing, follow these directions:
a) Use pulleys with V-belts with the size of the groove
required/recommended by the manufacturer of belt used.
In the absence of directions, follow Fig. 9 and the table in
Fig. 10.
Break
corners
Single groove Multiple groove
Fig. 9
41
Fig. 8