* Register your self at city hall where you will have an address. At this time, get a Certification of Registered Matters (Toroku Genpyo Kisai Jiko Shomeisho). Document needed to prove your address.
* Purchase motorcycle. The bike shop usually handles registration procedure for you.
* Get international registration from Land Transport Office (Rikuunkyoku)
* Get international license plate from JAF. This takes a couple weeks.
* Have someone deregister the bike after you leave. Otherwise you (or whoever’s address you are using will be billed for annual vehicles taxes).