The standard valve clearance is:
Intake: 0.05 mm (0.002 in)
Exhaust: 0.05 mm (0.002 in)
The Honda service manual specs adjusting the valves every:
2,400 - 3,000 miles (4,000 - 4,500 km)
We recommend performing the valve adjustments during every oil change at:
1,000 - 1,200 miles (1,500 - 2,000 km)
The valve adjustment must be done after the cam chain adjustment and before the ignition timing.