A bead seat clincher bicycle rim includes a tire supporting surface bounded by a first straight sidewall and a second straight sidewall wherein said bicycle rim does not comprise bead hooks. A method for forming a bead seat clincher rim includes forming composite plies in a bottom portion of a mold and placing a single piece upper portion over the bottom portion. A bladder is inflated in the center of the mold to form a closed cavity within the rim. The rim is cured and the bladder is deflated. The single piece upper portion and bottom portion of the mold are removed.