Yes, you can ride after a knee replacement. The amount of time it takes to be able to ride again will depend largely on the type and severity of your surgery. Generally speaking, most people can start riding again in 3-6 months following their procedure. However, if you had more extensive surgery or additional procedures such as ligament reconstruction or bone grafting, then recovery may take longer before riding is possible. Before getting back in the saddle, talk with your doctor about any restrictions that should be followed for safety and comfort during activity. Additionally, there are several ways to modify an exercise bike so that it is easier on your new joint; ask your physical therapist for advice on how to do this safely.