[weeder]

I think you are rolling two issues into one. The concept of peoples impressions of a female on the back of a motorcycle, or riding one, and reactions to styles of dress. There have always been those who abhor bikers and their bikes and there always will be. As far as clothing goes.. on a motorcycle or off. ...Often fashion choices are made to make a statement. And if that statement evokes feelings of fear, or agressiveness, or darkness, such clothing will receive the response it invited. I think that when a single person or couple rides down the road who are conservatively attired, nowdays.. they really do not draw any attention at all. People have always gawked at females dressed in revealing, or bold attire. That is why society is divided into groups. The old and the young. Conservative and liberal etc....
I think you will agree that reactions vary according to different areas of the country. In a bar in New York for example.... Motorcycle gang members can be shooting pool in the back, while businessmen in suits drink at the bar. No one pays much attention to anyone else. Let that same group of cyclists ride up to a tavern here, in sleepy, conservative Virginia and all heads would turn as if aliens had just landed.