I still using my petrol bike, by the time found some ways to get petrol. Still not perfect, sometimes i have to leave the bike at home and use the subway until next day until the time i'll get fuelled up. In Shanghai police recently stop me 3 times in the same point, Luban Lu X Xietu lu, but once they realize im foreigner they asked me to go, even after i have told them i dont have drive license and plates/regular documents. I visit clients during all day, sometimes running more than 100km in a day, and after expo, last year, fiscalization is not that hard anymore (but still exists and once u see police, better to avoid - and better take advantage that most of chinese are blind and normally, if u r not distracted, u see than much before they see u).

Also this bikes we r unable to put plates still being selled in Shanghai, i guess still ok to sell it once u still can get plates in small cities in China. What i mean is u dont need to live in Shanghai or Beijing to buy one and take to the small city you live and regularly get documents and plate.