Yamaha F15 Owner's Manual page 79

Maintenance
speeds, with sufficient time for engine warm
up and cool-down, a medium to light load,
and an average cruising speed near the
3000 to 4000 rpm range. As with any engine,
however, if your normal operating conditions
are different, you should consider service
more often than shown, especially how often
you change your engine oil and gear oil. Ex-
amples might include extended wide-open-
throttle use or long periods of trolling or
idling, carrying heavy loads, or frequent
starting and stopping or shifting. More fre-
quent maintenance will often pay off many
times over in increased engine life and great-
er owner satisfaction. Consult your Yamaha
dealer for additional maintenance recom-
mendations.
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