PIAGGIO Vespa 150 1962 Operation And Maintenance Manual page 24

Fig. 16 - Drive system
1. Gear change twist grip 2. Clutch control lever 3. Gear change control cables 4. Gear shifter
5. Selector stem 5. Selector 7. 1st gear pinion 8. 2nd gear pinion 9. 3rd gear pinion
10. 4th gear pinion 11. Main shaft 12. Cush gear 13. Clutch.
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