Abstract: A self unloading harvest cart transfers agricultural products from a harvester to an over-the-road vehicle. A tilting bin within the cart has a base defining four edges, and first, second and third sidewalls each rise from the first, second, and third base edges, respectively. The bin has a generally open face above the fourth base edge. A bin actuator rotates the tilting bin relative to an undercarriage about a first pivotal coupling. A conveyor sidewall encloses the tilting bin adjacent the base fourth edge, and has a conveyor that conveys agricultural product from within the tilting bin to the over-the-road vehicle. A conveyor sidewall actuator rotates the conveyor sidewall relative to the undercarriage about a second pivotal coupling. The conveyor sidewall is rotated away from agricultural product when or just prior to starting the conveyor, to reduce conveyor sidewall starting resistance and reduce the conveyor sidewall initial load.