What is the bike called that Marlon Brando rides on Andy Warhols silk screen?

I read somewhere, that Marlon Brando did NOT ride a Harley Davidson in this film...The Wild One (1953). Only the actor Lee Marvin rode a Harley.

Brando's bike was a big Triumph of the times.??

Wait, I'll find an internet proof....

Here is a larger photo for you. You can see the word "triumph" to the right of the headlight.

http://www.hondahog.com/wildone.htm

I would swear that the Brad Pitt photo with girl passenger is NOT a Triumph . the gas tank is my clue, doesn't look like other Triumph gas tanks. BUT I AM WRONG-O. Here is a movie review:

......There are a couple of motorcycles in the movie…at least from what I can view in the trailers. One is a Triumph Twin (Blue) and the other is a Flathead Indian (Red).

it was a british made Triumph.model either a 650cc or Bonneville not to sure about model though