YCF 50 A Owner's Manual page 92

English
Fuel Tank Cap
This component controls the fuel flow from the fuel tank to the carburettor.
ON OFF RES
ON
To start the engine, turn the fuel tap lever to the "ON" position to allow fuel to flow.
OFF
When you have finished riding, turn the fuel tap lever to the "OFF" position.
RES
Turning the fuel tap to "RES" allows fuel to flow from the reserve fuel supply to the carburettor.
Reserve fuel: 0.98 L (0.26 U.S Gallons) (it is imperative that you refuel as soon as possible to avoid running
out of fuel). Once you have refueled your Mini-Motorbike turn the fuel tap lever back to the "ON" position.
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