Comment by card_zero
Hmm. If the diameter of the circle that the car drives in is 14 meters, that works out as ... 54657 mph. I cannot endorse this from a safety standpoint.
Wait, no, I was working in km instead of m, it's only 54 mph. Should be fine.
It's one revolution every 1.8 seconds. That seems too fast for most roundabouts, but maybe not uncontrollably so.
78 rpm is Formula One territory.