Yamaha YFM350S Owner's Manual page 158

0–10 hours:
Avoid continuous operation above half throttle. Al-
low a cooling off period of five to ten minutes after
every hour of operation. Vary the speed of the ma-
chine from time to time. Do not operate it at one
set throttle position.
10–20 hours:
Avoid prolonged operation above 3/4 throttle. Rev
the machine freely through the gears but do not
use full throttle at any time.
After break-in:
Avoid prolonged full throttle operation. Vary
speeds occasionally.
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