Ran across these guys hanging out in front of a closed Emart late at night near Yongsan. The thing they’re riding is a Mototec Wheelman, powered by a small gas engine. They were wearing protective gear and custom LED lights all over to make sure they’re visible to traffic. Nice guys, one called himself Bulldoja (Bulldozer) and let us try riding. I could barely stay balanced on it, but these guys were doing all kinds of tricks with them.