Sorry you are wrong but I can make it right if you come to Chengdu, Here a license can be converted for 90 days per stay visa and here you CANNOT get Temp motorcycle license, and my understanding is that all China is meant to be the same.
I can get you registered at our home then get you the legal license etc assuming you pass the test, I can get and legally make you a Yamaha or other bike legally in your name with all papers documents and insurance etc.
I do motorcycle stuff in Chengdu (When it isn't retards asking or saying stupid shit etc)
Anyway I am going on the info that states you can have 90 days per stay each time you enter - If this isn't correct then my advise is nil and void.
I do charge for my work etc but I think you will find it reasonable - All things with a license and all fee's 1000 yuan per person also a bike plus costs and 1000 yuan per bike - ALL legal in YOUR name etc.