Movable partition systems include an elongated drive member with fixed, offset ends extending along a track, a partition that is automatically and manually movable along the track, the partition hanging from a trolley disposed at least partially within the track, a motor carried by the movable partition configured to drive a rotatable drive member engaged with the elongated drive member, and a clutch coupled with the motor configured to engage or disengage the rotatable drive member from the motor. Methods of moving a partition along a track include actuating a motor carried by a movable partition to drive rotation of a drive member while a clutch mechanism is engaged, and manually moving the partition along the track while the clutch mechanism is disengaged. Methods of installing a movable partition system include coupling a trolley to a rotatable drive member and placing the trolley within a channel of a track.