The Fucoff Skatestop Removal Set offers a solution to getting these downtown ledges back in shape. Inside a compact red rubber box you will find 32 bits most commonly used for applying/removing stoppers on/off a ledge or a rail, as well as an adapter to attach the bit to a power tool or a portable handle.
Unlock the long gone and forgotten spots and put some energy out on the streets. And if you want to keep it low-key, just put the stoppers back on after session to avoid heat.