No Dogs on Bicycles

So I was doing a little research at work yesterday; a project I am working on includes a dog park and I needed to find some signs for it.

As I searched through some images on the internet I noticed this one. Only it wasn't quite this one - it was a sign, about the size of a "No Parking" sign, on a steel post. The type of sign you would expect to see at a park. Only it wasn't quite what you would expect to see. I mean, dogs on bicycles? 

My first thought was, "who would put a sign like that in a park?" My second thought was, "where is this place that has a problem with dogs riding bikes?" My third thought concerned the problem of dogs riding bikes. "What is the problem, exactly. Are they careless? Do they bolt off on a tangent unexpectedly in pursuit of squirrels and cats? Is the problem only with the long, floppy ears of basset hounds getting caught in spinning wheels?" "Do the greyhounds go too fast around the younglings and old folks out for a Sunday stroll?" It is a curious thing, and my fourth thought was, "this is a place I want to see." Next I thought, "Curious that there is a similar sign stating 'No Dogs, No Bicycles' - that is just boring." After that, I ran out of thoughts, but recovered a few moments later, just long enough to wonder if I could sneak such a sign past the city planners of Chino Hills.