Yamaha BIG BEAR PROFESSIONAL 400 YFM400FPT Owner's Manual page 178

Riding your ATV requires skills acquired
through practice over a period of time.
Take the time to learn the basic techniques well
before attempting more difficult maneuvers.
Not recommended for children under 16 years
of age.
WARNING
_
A child under 16 should never operate an ATV
with engine size greater than 90cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death of
the child.
_
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