[flavius29663]

Aren't monowheels very nasty when you fall? If it gets stuck you will just flop at high speeds.

[oblio]

Why would you get stuck, though? I'd assume that you can jump off. The high speeds part is risky, but if you don't go fast (15-20km) I assume you should be ok?

[k__]

Also, they probably aren't even legal to ride.