I went through a speed trap setup at the bottom of the A30 going into Yatley/Camberley many years ago. Bloke with a hairdryer looking a bit confused. Stopped further down the road. I was told I had been doing 43 into a 40 limit and would be contacted in due course (not old enough to have a driving licence).
They duly came around (mum had a fit and dad had a laugh at the speed I achieved) and tried to give me a borrocking. I did the nod with respect thing and then tried to work out if I could fit a speedo to my bike to beat it in the future.