Thanks for your reply.
I have a visa for 90 days.
My cycling route length is about 6000 km. as you know, it`s long bicycle trip. also it`s tight schedule.
If i`m staring Okinawa first, i will expire visa.
In the worst case, ALPS road except from cycling route. instead, i will choose Tokaido route.
Anyway, thanks for your advice.