There are "rules of the road" here regarding bikes, the problem strives on finding someone following them.

Now, to qualify my statement above, must give you a bit of an explanation.  legally, private individuals can have bikes up to 250 cc and drive them on the streets without risking confiscation.  That's the rule.  Now, depending who you are, who you know, and how "rich" you are, you could do as you please, since when bike is confiscated by street traffic cop, will be returned to you at the Police Station if your "guangxi" works.  It is a well knwon fact that in Beijing there is a Harley Davinson dealership selling bikes, and if you buy one to can keep it at home as  status symbol, but can not legally ride it if over 250 cc.

Now, in regards to your comments about Behai.  You are partially correct.  You are most probably referring to Tommy, a dear friend, owner of the famous Tommy's Bar and Restaurant on the bayfront, and one hell of a nice guy.  He had two Harleys, and another one and I forgot the trademark.  But he imported them into China legally, obtained for them "exhibition" or show license plates, which allowed him to ride them on the streets on the way to a bike show to display them there.  He had the muffler removed on at least one if I recall right, and was quite loud, and a nice roar announcing his approach.  And he rode it as he pleased, day and night.

But agravations and problems took its toll, and he eventually got rid of the two Harleys, and the third hangs from the ceiling at the entrance of his eatery.

Just remember, where you live and what you do is important in this "guanxi" business.  In a big city, it takes and demands a lot of time and effort, and it will "cost" you more,  In smaller cities and towns, it will be easier and cheaper to develop, and if you own a business, even better.