Adjust the engine idle speed periodically on the engine at normal operating temperature.
To adjust the idle speed:

Engine oil and filter change
Throtile cable playCrankcase emission control system
description
The engine is equipped with a pcv system to prevent discharging crankcase
emissions into the atmosphere. Blow-by
gas in the engine is constantly drawn into the crankcase, which is returned to
the combustion chamber through the
pcv (breather) hose, air cleaner and throttle body.
...
Excva pulley inspection
Inspect the excva pulley in the following procedures:
remove the excva pulley. Refer to “excv cable removal and installation”
.
Visually inspect the excva pulley for wear and
damage. If there is anything unusual, replace the
pulley with a new one.
Install the pulle ...
Clutch cable play inspection and adjustment
Inspect clutch cable play
every 6 000 km (4 000 miles, 12 months)
Inspect and adjust the clutch cable play “a” as follows.
Clutch cable play “a”
10 – 15 mm (0.4 – 0.6 In)
Lift and support the fuel tank. Refer to “fuel tank
removal and installation” in section 1g (page 1g-
9).
  ...