Honda TRX420TM Owner's Manual page 75

Riding Your ATV
Shift weight forward when climbing hills.
Always check the terrain carefully before you start up any hill.
Never climb hills with excessively slippery or loose surfaces.
To climb a hill, take a running start in an appropriate gear and speed
for the conditions. Maintain a steady speed as you ascend the hill.
Never open the throttle suddenly or make sudden gear changes. The
ATV could flip over backward.
Never go over the top of any hill at high speed. An obstacle, a sharp
drop, or another vehicle or person could be on the other side of the
hill.
Basic Operation & Riding
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