So I have this question regarding the traffic cops sitting on a stretch of road where they catch every second person, it's in the middle of no where, no school, no nothing, just farm land. 
Now driving either way there is no speed limit signs 10km in any direction, I stopped and asked them what is the speed limit, they informed me it is 80km/h.
Is this legal at all with no speed signs?
I went through these document, but didn't see any thing.
http://www.speedtraps.co.za/docs/Guidelines_regarding_laser_speed_measurement.pdf
http://www.arrivealive.co.za/pages.aspx?nc=prosecuting
Now driving either way there is no speed limit signs 10km in any direction, I stopped and asked them what is the speed limit, they informed me it is 80km/h.
Is this legal at all with no speed signs?
I went through these document, but didn't see any thing.
http://www.speedtraps.co.za/docs/Guidelines_regarding_laser_speed_measurement.pdf
http://www.arrivealive.co.za/pages.aspx?nc=prosecuting