Abstract: A position detection device for a bicycle may include a bicycle component defining an interior and an exterior. A detectable element may be disposed in the interior of the bicycle component and movable relative to the bicycle component. At least one detecting element is disposed in the exterior of the bicycle component, the at least one detecting element operable to detect: a first position of the detectable element relative to the bicycle component, and a second position of the detectable element relative to the bicycle component, wherein the second position is different from the first position.