Honda HRS21 Owner's Manual page 34

Throttle Control Cable Adjustment
1. With the throttle lever in the START (CHOKE) position, the carburetor
choke arm should move all the way to UP, as far as it will go. Push the
control, lever with your finger to check whether it is all the way to UP.
CHOKE ARM
CONTROL LEVER
2. If adjustment is necessary, loosen the control cable lock nuts, and move
the adjuster up or down as required. Tighten the lock nuts, and recheck
the carburetor choke arm position.
LOCK
NUTS
AbJUSTER
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