Honda CRF250F Owner's Manual Installation And Operation page 204

BATTERY
Refer to the Safety Precautions on page 43.
It is not necessary to check the battery
electrolyte level or add distilled water as the
battery is a maintenance-free (sealed) type.
If your battery seems weak and/or is
leaking electrolyte (causing hard starting or
other electrical troubles), contact your
dealer.
Your battery is a maintenance-free type and
can be permanently damaged if the cap strip
is removed.
The battery gives off explosive
hydrogen gas during normal operation.
A spark or flame can cause the battery
to explode with enough force to kill or
seriously hurt you.
Wear protective clothing and a face
shield, or have a skilled mechanic do
the battery maintenance.
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