Abstract: A bicycle has a frame comprising a head tube, a bottom bracket tube, a top tube, and a down tube that are pivotally connected to form a four bar system. The bicycle further includes a saddle that is attached to a seat post and pivotally connected to the top tube. By tilting the bottom bracket tube downwards the head tube is also pulled downwards, and the bicycle is brought from a normal position to a recumbent position. Tilting the bottom bracket tube downwards takes place by exerting a force, for example the user's weight, on the saddle. This force is transmitted to the bottom bracket tube through an auxiliary connecting bar, which is pivotally connected to the seat post and the bottom bracket tube.