Had a guy that would show up (usually late) for a group ride on some Frankenstein e-bike he had cobbled together with parts from who knows where. It was a hub drive, and the control was ON or OFF. He had a huge battery pack strapped onto the frame with heavy external wiring zip tied and taped at various points.

The thing must have weighed close to 50 pounds, if not more. On the ride, he would leave the motor off on the flats and drag everyone down because he couldn't maintain pace, claiming he was "saving his battery for the hilly parts" of the route, at which time he would turn the motor on and blast past us up the climbs without even pedaling. Of course, he refused to use any type of bike computer with GPS, so he would on occasion miss a turn after his electrified sprint and get lost. Inevitably, someone would have to go on a search and rescue mission to find him.

People finally got so fed up that we would announce a ride at a certain time and show up at least an hour early to leave. He would show up, find no one there, and later complain. Eventually he stopped showing at all.