Not a bad idea. We live on a rural road that is on maps for cyclists. On days with decent weather there can be dozens of cyclists on many of the roads here. Most of them abide by the single file rule, but some are just assholes. The roads are barely wide enough for 2 cars and idiots ride their bikes 2 or more abreast. Beep the horn once or twice to let them know you’re coming, and they flip you the bird. Not much you can do other than run them off the road, but a friend had an excellent idea, he had a beater car with the old windshield wiper nozzles mounted on the hood that you could bend. He bent the one on the passenger side and would spray obnoxious cyclists that gave him a hard time. They would come to a sudden stop and the ones behind would crash into them.
The roads were narrow, some had sidewalks but only on one side. Topography was very steep. The main thoroughfare in the area was a narrow two-lane, ran along the river ridge, many blind hills and blind curves. But the idiots at the local bike shop actually *sponsored* a regular ride the length of this road.
One fine day, I come over a hill to find a gaggle of cyclists riding 6 or 8 abreast, the inside guy was in the middle of my lane. I jammed the brakes and hit the curb so the guy wouldn't become a hood ornament. He and 2-3 others shot me the bird.
I drove right down to the local cycle shop. Told them what had happened, told them I was filing a police report, and also told them that they would be held responsible if somebody on one of their sponsored rides got injured or killed.
I must have made an impression (I was very polite and collected. Didn't litigate for 30 years without learning to keep my temper). The rides stopped. Now you only see 2-3 guys instead of 20.
We drive regularly on a two-lane road through a national park. The road is curvy and hilly and often bicycle-infested. To me the worst annoyance is not the cyclists so much as the wuss drivers who won’t just pass them, instead creeping along behind them for sometimes a mile or more.
In Arizona the law is that cars aren’t allowed to pass a cyclist within three feet. My view is that cyclists should therefore be forbidden to ride on any road where the shoulder is not wide enough for a cyclist to remain at least three feet outside the traffic lanes, unless the cyclist is able to maintain the speed limit at all times.