PIAGGIO Vespa 150 1962 Operation And Maintenance Manual page 27

Brake adjustment. Brakes are properly adjusted if:
- The wheel rotates freely when control lever or pedal are in resting position; and
- The braking action starts as soon as controls are operated.
These conditions are obtained by adjusting the tuning screws on the cables (see Fig. 18).
Fig. 18 – Brake adjustment
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