Welcome NC-redleg

Two things need to be considered:

1) The bike has to be on an "approved list" of motorcycles for registration. Not many bikes are. It is a complicated issue, but relates primarily to emissions, as well as manufacturing/import taxes being paid.

2) Assuming the bike is "on the list", is a genuinely legal bike (i.e., not an illegally imported one), and it can be legally registered in your city of residence (some cities just say no to bikes), the tag price varies dramatically. In little towns, it may be as low as a few hundred rmb (about $20). In large cities, it can be very expensive (e.g., Shanghai is >50K rmb ... about $7,500 US; in Beijing it is about 20K rmb ... about $3,000 US). The reason the price is so high is because there are a fixed number of tags available in these major cities, and only in the secondary market (no new ones are being issued).

Bike registration/insurance is a whole different kettle of fish in China. It is complicated & expensive and, largely for that reason, many people opt to ride illegally.

In the past, the police largely ignored this "issue", but that has changed. Now, it has potentially quite serious consequences.

Those R9s are like mosquitoes in certain areas of Beijing (e.g., WDK) - annoying.