I didnt know that either, they definitely arent designed for it! Can you imagine how hard that little DC motor has to work?! In a city I used to live in there was a really big, long hill that a popular strip mall was on and I would often see fats "stuck" on the hill when their scootypuff ran out of juice, and I would honk and laugh. I always wondered what they did, god forbid walk. Maybe they called a special AAA for fats, XXXL-AAA or something