Polaris Frontier Classic Owner's Manual page 61

Engine Break-In
No single action on your part is as important to long, trouble-free
machine life as proper break-in of a new or rebuilt engine. During the
first three hours of operation, operate the snowmobile as outlined in
this Engine Break-In section.
Failure to follow the procedures outlined in the Engine Break-In
section of the owner's manual could result in serious damage to
the snowmobile. Follow all procedures as outlined.
Avoid Heat Build-Up
Excessive heat build-up during the first few hours of operation will
damage close-fitted engine parts. Do not operate at full throttle or high
speeds for extended periods during the first 100 miles (160 km)of use.
Vary the throttle openings and machine speeds to reduce friction on all
close-fitting machined parts, allowing them to break in slowly without
damage.
Perform Fluid Checks
Perform regular checks on fluid levels, lines, and all other important
areas of the machine. Perform the first oil and filter change at 500
miles (800 km). See page 83.
CAUTION
OPERATION
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