A harvester roll structure composed of a gear housing and a rigid elongated shaft sleeve fixed to the gear housing which supports a roll drive shaft. The drive shaft has one end projecting from the sleeve. A hollow harvesting roll is fixed to the exposed end of the shaft and projects therefrom over and in surrounding relationship to the sleeve. Fixed to the sleeve and projecting into the spacing between the sleeve and the hollow roll is a spiral rib which cooperates with the roll as it rotates to expel material from the spacing between the sleeve and roll.