Originally Posted by biknut
Tankers, I like that Pat. I'm not sure why they're called three bar frames. Isn't there only two bars?
Your first picture of the Schwinn Panther is called a three bar frame because it has a top tube, middle tube, then the down tube in the front frame triangle. Also called a straightbar frame as the center tube just below the tank is straight. The Schwinn DX frame middle tube is curved.