Abstract: The present invention disclosed herein comprises a sprocket having circumferentially spaced teeth that are axially aligned and engageable with a positive drive belt, the sprocket having first and second guide flanges extending radially outward on opposite sides of the sprocket and a spacer member disposed adjacent to the first guide flange, encircling the sprocket and engaging the teeth of the sprocket such that the positive drive belt is disposed between the spacer member and the second guide flange, thereby reducing the required width of the positive drive belt.