Just a reminder that the M1 gantries are live between Nottingham and Sheffield. Even when not displaying a reduced speed.
Given that about 30% of the traffic is doing about 80 mph when there is not a lower limit posted they must be raking it in. The limit on the Autostrada in Italy (and many other countries) is 130 kph (80.8 mph) it is not surprising many drivers feel quite comfortable at that speed.
I'm sorry to say I have lost count of the number of speeding fines I have had, all in Oz plus 2 in hirecars in the UK despite being very careful. I find it difficult to relate to miles per hour after driving in kilometres since 1974. The TV ad was even in black and white back then, colour TV was introduced 1 March 1975