Polaris 340 Touring Owner's Manual page 64

Fuel
Your Polaris engine is designed to run on 87 octane non-oxygenated or
89 octane oxygenated pump gasoline. There's a great deal of variability
in the quality of the 87 octane gasoline available across the country, so
we encourage the use of premium fuel when possible. Do not use fuel
containing more than 10% ethanol (including E85).
NOTE: Some engines require premium fuel. See your Owner's Manual
Supplement.
Using fuels with a lower than recommended octane or operating with
obstructed fuel systems will result in serious and costly engine damage.
Always use the recommended fuels for your machine.
CAUTION
OPERATION
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