A system for controlling bicycle tire air pressure on the go is provided. The system has a wheel mounted portion and a control unit in wireless communication with one another. The wheel mounted portion attached to each wheel has a gas source, manifold, regulator to control air flow into and out of the tire, and a wireless communication device. The control unit monitors air pressure in each tire, and has a user interface allowing input of a higher or lower tire pressure. Based on user input, the control unit instructs operation of the wheel mounted portion, controlling pressure within the tire.