Honda CRF125F 2020 Owner's Manual page 143

SYMPTOM: Starter motor works, but the engine won't start.
POSSIBLE CAUSE
out of fuel
flooded engine
loose or unconnected
spark plug cap
loose battery cables
weak battery
SYMPTOM: Engine starts, but runs poorly.
POSSIBLE CAUSE
idles roughly, too fast, stalls
runs erratically, misfires
blubbers (rich fuel mixture)
Taking Care of the Unexpected
Fill the fuel tank.
See
Install the spark plug cap securely. If the engine still
won't start, see your dealer.
Tighten the battery terminal bolts.
Charge the battery (page 114). If charging doesn't help,
see your dealer.
See your dealer.
See your dealer.
See your dealer.
WHAT TO DO
(page 33).
WHAT TO DO
Taking Care of the Unexpected
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