A generic manual will lead to incorrect oil ratios, seized engines, or poor performance. You must find the (workshop manual) specifically for the Piaggio Liberty 50 2T air-cooled .
: Capacità di circa 6 litri (di cui 1,5 di riserva). Batteria : Solitamente di tipo 12V 4Ah (es. modello YB4L-B). Pneumatici : Posteriore standard 110/80-14.
There are two versions of the manual. You need both.