An exercise bicycle including a frame, an adjustable seat structure, and an adjustable handlebar structure. One example of the frame includes a front fork, a down tube connected with the front fork, a seat tube, and a bottom frame member. The down tube has a first section that extends downwardly and rearwardly from a top portion of the front fork and has a section horizontal section connected with the seat tube. The front fork, down tube, seat tube, and bottom frame member define a five sided structure. The frame also includes a rear support brace connected with the seat tube and the bottom frame member in a triangular configuration. The seat structure has a seat post that is adjustably supported in the seat tube. The seat structure also has a horizontal seat rail and a cooperating seat collar that slides back and forth on the seat rail to allow fore and aft adjustment of a seat connected with the seat collar. The handlebar structure is adjustably supported in the a head tube, which is connected to the top of the front fork, and provides a plurality of gripping positions for a user.