The amount of backlash can be changed by turning the balancer shaft which has eccentric journals.
Start the engine and let it idle.
Loosen the clamp bolt [A] and turn the balancer shaft [B] clockwise [C] until the balancer gear makes a whining sound.
Turn the shaft counterclockwise [D] until the balancer gear whining sound disappears and tighten the clamp bolt.
Torque - Balancer Shaft Clamp Bolt: 9.8 N·m (1.0 kgf·m, 87 in·lb)

Balancer Installation
Balancer Damper InspectionRebound Damping Force Adjustment
To adjust the rebound damping force, turn the rebound
damping adjuster [A] to the desired position.
The standard adjuster setting is the 1 3/4 turns out from
the fully clockwise position.
Rebound Damping Force Adjustment
...
Piston Ring, Piston Ring Groove Wear Inspection
Check for uneven groove wear by inspecting the ring seating.
The rings should fit perfectly parallel to groove surfaces.
If not, replace the piston and all the piston rings.
With the piston rings in their grooves, make several measurements
with a thickness gauge [A] to determine pisto ...
Rebound Damping Force Adjustment
To adjust the rebound damping force, turn the rebound
damping adjuster [A].
The standard adjuster setting is the 3 3/4 turns out from
the fully clockwise position.
WARNINGIf both adjusters are not adjusted
equally, handling
may be impaired and a hazardous condition may
res ...