It's not quite as bad as the picture makes it look but it is still significant.
I guess it must be because it was on the inner side of the wheel.
Probably a pothole and it must have happened within a couple of days after I put them on the car over 18 months ago, as I noticed a vibration at 75+ pretty soon after fitting them. Thought it must me something else causing the vibration like an engine mount especially as it wasn't visible. I had got them refurbished and swapped the rubber over so it was definitely ok when it went on the coop. Anyway a niggling problem has now been solved.