Captain America's motorcycle from the 2011 movie "Captain America: The First Avenger" was based on the 1942 Harley-Davidson WLA used in World War 2. I modeled this bike following along to an excellent course by Darrin Lile on Udemy.
This has definitely been my most time consuming project to date, but it was a great deal of fun every step of the way. ...not to mention a great learning experience.
Modeled in Blender 2.79. Rendered in Cycles. Minimal post-processing in Photoshop.