This isn't strictly a 'motorcycle' story but at least THE COPS were on motorcycles, and we all were on two wheels, anyway.

Anyway, back in the early 1980’s, I was in college in the San Fernando Valley in California and my main mode of transportation was my 18-speed bicycle, which I rode like mad everywhere.
One evening, I was riding south on Reseda Blvd. It was downhill, so I was going at a pretty good clip. A couple of motorcycle cops were sitting on their Harleys on a side street, and one raised his hand. I waved back and continued on.
The next thing I knew, they were beside me with their lights on. I quickly went up a driveway and stopped on the sidewalk.
The following conversation ensued:
Me: “I’m deaf!” (I always announce that to cops so that they know there may be a communication issue.)
Cop #1: “Does that mean you’re blind, too?”
Me (indignant): “NO!”
Cop #2: Laughing
Cop #1: “Didn’t you see me wave you down back there?”
Me: “Yeah! I thought you were being friendly and all.” (Note the naiveté?)
Cop #2: Laughing.
Me: “So, what’s the problem?”
Cop #1: “Why don’t you have a light on your bike?” (It was dusk, so I could see his point.)
Me: “I’m a student! I don’t have money for a light!”
Cop #1: “Well, get one, anyway! You can’t be riding in the dark!”
Me: “OK!”
Cop #1: “OK!”
Me: “Later!”
Cop #1: “Later!”
I never did get that light, instead taking care not be caught out at night.