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 InspectionWater Temperature Sensor Resistance Inspection
Refer to the Water Temperature Sensor Inspection in the
Electrical System chapter.
If the reading is within the standard, but the problem still
exists, replace the ECU (see ECU Removal/Installation in
the Fuel System (DFI) chapter).
Water Temperature Sensor Circuit
1. ECU
2. Water T ...
Release Shaft Installation
Apply grease to the oil seal lips on the upper ridge of the
clutch cover.
Apply engine oil to the needle bearings in the hole of the
clutch cover.
Applymolybdenum disulfide grease to the pusher-holding
portion [A] on the release shaft.
Install the washer [B] and spring [C].
...
Serial number locations
The engine and frame serial numbers are used to register the motorcycle.
They
are the only means of identifying your particular machine from others of the
same
model type. These serial numbers may be needed by your dealer when ordering
parts. In the event of theft, the investigating authoriti ...