If I want to go back in time, I enjoy riding my old Osgear bike. I place the frame in the late 40's (but could be earlier) and the Osgear is 1950.
The bike is quite light (22Lb) and well built and the Osgear is 4 speed and changes very reliably. The seat tube angle is 71 degrees and is very comfortable. It rides like a 1980's bike.