You need a crew of armed bikers to migrate to the area. The word of a few dead perps littering the sidewalk would get around the hood pretty fast.
Harley-type bikers and Schwinn-type bikers aren’t the same, usually :-)
... though maybe the human powered cyclists could take to wearing spikes... as a warning. Don’t mess around with Spikes ‘n’ Spokes. One idea, don’t know how good or bad it would be. The spiky bikers might attract more attacks, not less, by ground based dudes with ‘tudes. No easy answer down this road.
WWJD? I dunno. Other than pray before and while riding. Even peaceniks have some sort of limit.