Dropperpost

A dropper post, also known as a dropper seatpost or adjustable seatpost, is a bicycle component that allows the rider to adjust the saddle height on the fly. This is achieved through a mechanical or hydraulic system controlled by a lever, usually mounted on the handlebars. The primary benefit of a dropper post is improved descending capability and maneuverability. By lowering the saddle, the rider can move their center of gravity lower and further back, giving them more control and confidence on steep or technical descents. It also makes it easier to dismount quickly.

Dropper posts are commonly found on mountain bikes, particularly those designed for enduro, downhill, and trail riding. However, their use is expanding to other cycling disciplines like gravel biking where varied terrain might benefit from on-the-fly saddle adjustments. The mechanism typically involves an internal cartridge that contains either air or oil pressure to assist in moving the seatpost up and down. The control lever actuates a cable or a hydraulic line, which in turn releases a valve allowing the post to move. When the valve is closed, the post locks in place at the desired height. Early dropper posts were often heavier and less reliable, but modern designs have become significantly lighter, more durable, and smoother in operation.