Here’s a video of the Key Town Cruisers (Leiden), the Rollin’ Daddies (Leiderdorp) and Chopaderos (“worldwide drinking club with a bicycle problem”, Amsterdam) on their yearly bock beer tour.
I had no idea choppers still existed. It seems they’ve not only survived the 1970s, but have gotten fashionable in the interim. These mean machines look like they could take on a bakfiets!