) 
The black bit with the white line was just starting to wind down when his mate, who was red with a white bicycle painted on, start effing and blinding for no apparent reason. He then stands up and throws his drink against the wall before quietly walking out as if nothing has happened.
The barman rushes over and asks the black piece what on Earth was the matter with his mate.
"Don't worry", he said, "He often does that, you see he can't help it...he's a little bit of a cycle path"
