Polaris 120 Owner's Manual For Maintenance And Safety page 52

Operation
Speed/Performance Regulation
Adults have the responsibility for teaching children the proper and safe
way to ride a snowmobile. Please set boundaries and adhere to them,
keeping your child's safety foremost in your mind. Never allow a child
to operate this machine without adult supervision.
Under certain circumstances it may be necessary for an adult to
regulate the speed and acceleration of the snowmobile by moving the
governor lever spring. Use the following procedure to set the
performance level.
CAUTION
Hot engine components can cause serious burns to skin. Always
perform the following procedures when the engine is cool.
For maximum performance,
move governor spring (A) to
hole #3.
For minimum performance
move governor spring to hole
#1.
ADULT SECTION
3
1
A
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