Everything on the net says it was a Harley. In the picture there it shows him standing next to a 450 Rebel.
Call me someone from the "Show Me State" but, I'll have to watch & see if he was actually riding it.
I saw the movie again, he is definitely riding it. and it's a Rebel 450. He must be an avid rider because he has been on bikes throughout various movies in his career, but this is the first time on a Honda LOL.