Yamaha GRIZZLY 80 YFM80GT Owner's Manual page 142

If any abnormality is noticed during this period,
consult a Yamaha dealer.
0-10 hours:
Avoid continuous operation above half throttle.
Allow a cooling off period of five to ten minutes
after every hour of operation. Vary the speed of
the machine 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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