Honda EB2000i Owner's Manual page 53

Service according to the table below:
STORAGE TIME
Less than 1 month
1 to 2 months
2 months to 1 year
1 year or more
*Use gasoline stabilizers that are formulated to extend storage life.
Follow the manufacturer's instructions for use.
Contact your authorized Honda generator dealer for stabilizer 
recommendations.
RECOMMENDED SERVICE PROCEDURE TO
PREVENT HARD STARTING
No preparation required.
Fill with fresh gasoline and add gasoline
stabilizer*.
Fill with fresh gasoline and add gasoline
stabilizer*.
Turn the engine switch to the OFF position
and drain the carburetor float bowl (see page
52).
Drain the fuel tank and carburetor (see page
53).
Change the engine oil and lubricate the
cylinder (see page 41).
STORAGE
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