Abstract: An adjustable bicycle seat includes first and second support platforms laterally separated by first an second relatively slidable, horizontally oriented, overlapping flanges respectively joined to the first and second support platforms and having a bolt extending through a passage therein to releasably secure the first and second platforms in laterally spaced relation. Each support platform includes an integral spring rotatably mounted in a clamp attachable to a bicycle frame. Apertures formed in the first and second flanges are selectively alignable when the bolt is removed from the passage to permit selective lateral and angular positioning of the first and second support platforms in a horizontal plane, and the bolt is engageable in the aligned apertures to secure the support platforms in such position.