Honda HSM1590i Manuel De L'utilisateur page 22

Throttle control lever
Use the throttle control lever to adjust the engine speed and/or snow
discharge distance with the mode selector switch set at the POWER or
SELF position.
Note that the engine speed and snow discharge distance cannot be
adjusted by operating the lever when the AUTO mode is selected.
Moving the throttle control lever to the FAST side increases both the
engine speed and snow discharge distance.
Moving the throttle control lever to the SLOW side decreases both the
engine speed and snow discharge distance.
SELF
···
F F A A S S T T
···
S S L L O O W W
THROTTLE CONTROL LEVER
POWER
···4th
(Long)
··· 3rd
··· 2nd
··· 1st
(Short)
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