Bicyclists are just too threatening for police to stand having around, doing their own thing. Bicyclists are pretty generally smart, fit, and independent, and there is nothing police hate more than a smart, healthy person breaking laws for a totally reasonable cause, with no victim. Here in Milwaukee, a couple weeks ago, the police arrested someone who organized an alleycat here in Milwaukee, citing him for disorderly conduct or something ********. In reality, though, it was obvious that they wanted to try and break up the 65 or 70 people who had arrived and been hanging out with all their bicycles in the parking lot.

Personally, if this happened in my town, I'd change the night of the ride discreetly, making sure that no police informants found out. If the new day gets busted as well, chances are that there is an informer at some level, and rides should be kept smaller. Breaking up into small groups on a whim would be entertaining, but only if you are all obeying the laws while under observation. It sounds like the police at that particular event were ready for a riot, and short of arming every bicyclist with a semi automatic weapon, it sounds like there was no real way of eliminating the police presence without dispersing the ride. Maybe it would be possible to file a complaint with the city. It's a huge waste of resources for them to ruin peoples' weekly fun by driving a bunch of gas powered vehicles along for the ride.