Honda Power Products WX15T Manuel De L'utilisateur page 14

Recommended Oil
Use 4-stroke motor oil that meets or exceeds the requirements for API
service classification SE or later (or equivalent). Always check the API
service label on the oil container to be sure it includes the letters SE or
later (or equivalent).
AMBIENT TEMPERATURE
SAE 10W-30 is recommended for general use. Other viscosities shown
in the chart may be used when the average temperature in your area is
within the indicated range.
CAUTION:
Using nondetergent oil or 2-stroke engine oil could shorten the engine's
service life.
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