My bike is now 20 years old, 84,000 miles, and I am not sure the timing belts have ever been replaced.
FYI
Manual calls for inspection at 100K miles. But most have because of age (20 yrs) or miles (100K), and almost all have found nothing wrong with them. But due to their cost when bought from other than Honda, are inexpensive enough to just replace them when you inspect.
There's some tricks in doing the job. Search, read and ask.
My IS was done at 100K. My GW was done after 25 yrs with 66K.