Honda HSM1590i Manuel De L'utilisateur page 24

SELF mode:
When the workload increases while clearing the snow, the engine
speed and snow discharge distance drop below the given speed and
distance that have been set with the throttle control lever. Reduce the
workload applied to the snow clearing part of the snowblower to hold
the engine speed/snow discharge distance at the given speed/distance.
If you are not sure of the appropriate position to set the engine speed
and snow discharge distance, we recommend that you set the control
lever in the third position from the bottom (maximum power position).
Then, adjust the snow discharge distance at the desired position while
you are clearing the snow.
···
FAST
··· 3rd
···
SLOW
SELF mode THROTTLE CONTROL LEVER
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