Originally Posted by
AlwaysAisle
JR East has an inspection car called E936 Series (nicknamed East-i) which runs on Tohoku and Jyoetsu Shinkansen. It is not yellow in color, and nobody seems to give a damn about E936 where "Dr. Yellow" enjoys celebrity status.
JR East E936
Becusee it is too normal looking, paint it a striking/stand-out colour and it would rise in fame.

(picture from the Internet, not mine. I just learned about this one today)