Honda BF9.9A Owner's Manual page 15

Fuel Recommendations
Use unleaded gasoline with a pump octane rating of 86 or higher.
This engine is desi ned to operate on unleaded gasoline. Unleaded
gasoline produces ewer engine and spark plug deposits and extends
9
. exhaust system life.
Never use stale or contaminated gasoline or an oil/gasoline mixture.
Avoid getting dirt or water in the fuel tank.
Occasionally
Y
ou may hear light "spark knock" or "
rapping noise while operating under heavy loads. T It
inging" (metallic
is IS no cause for
concern.
If spark knock or pin
normal
load, than
ing occurs at a steady engine speed, under
persists, see an aut
1
e 13 rands of gasoline.
If spark knock or pinging
orized Honda dealer.
Running the engine with persistent spark knock or pinging can cause
engine damage.
Running the engine with persistent spark knock or pinging is misuse,
and the Distributor's Limited Warranty does not cover parts damaged
by misuse.
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