Hussar gap 

Going less than 20km\h over the speed limit, which is forbidden and not fined in Russia at the same time, serving only as aggravation in case you have an accident. Named after hussars, who were a branch of imperial cavalry in Russian Empire. Most of the cars you see on road will be driving at speeds 10-15 km\h higher than the signs allow, thanks to the existence of hussar gap.

You can't get fined going 78 in a 60 zone in Russia, because technically you're goin in a hussar gap. So, on a 110 highway you can speed up to 128, even under cameras. But if you go 131, bam, fine in your mail the next week.

Hussar gap by Winjin July 5, 2017