I have driven the new Yaris Cross around south London quite a bit recently and have noticed something quite concerning. There are a number of main roads which are 40 or even 50 mph (part of the South Circular, for example) with side roads at 30 or even 20.  A few of these side roads have the speed limit pointing towards the main road and the car is picking these up and bonging at me.  My wife regularly drives past a primary school which has a sign nearby showing 20mph when there are lights flash