In the late 70s I used to ride my bike (a BSA Bantam D14/4 since you ask) along the Cromwell Road at West Kensington.
For about three months, there was a HUGE poster billboard by the lights at Warwick Road saying something like, "While you're waiting for [[i]something or other, can't remember what[/i]], here's a Wok in the Black Forest."
The HUGE poster was of a wok dropped onto a gateau.
I laughed every time I rode past it.
Mind you, I was younger then of course.