I just finished a ride similar to one I did about a month ago... there was a surprising difference. Many of the drivers were far friendlier. Even had one driver of a huge jacked up pickup truck give me a nod and a wave. Other cyclists were also more friendlier, I noticed a lot more waves.

The last ride was also on a Saturday, about 2 hours later in the day, and the traffic was just a bit heavier.

So what was the difference... Appearance wise I was riding my drop bar thin tire bike "racing bike" and a new jersey. I was only going about 2-3MPH faster than my other bike.

My other bike, that I used earlier, is a flat bar fat tire touring "truck." When I rode my "truck" I was wearing an orange longsleeve cotton T shirt, and one of those bright yellow vests.

There was one other slight difference... my flat bar bike has a mirror, my drop bar bike does not have a mirror... but certainly most of the motorists I dealt with were not behind me... thus it was not as if in looking back I got these reactions.

Now this is not to say that all motorists were wonderful... some still passed way too close. But the positive reactions far outweighed the negative.

So is it possible that wearing a bright jersey (I have always worn lycra shorts... just so comfortable) and being on a dropbar "racing bike" presents a more "professional" image, one that motorists can more relate to?