var scrollSpeed = 20; 		// Speed (70)
			var step = 1; 				// How many pixels to move per step
			var current = 0;			// The current pixel row
			var imageHeight = 1240;		// Background image height
			var headerHeight = 176;		// How tall the header is.

			var restartPosition = -(imageHeight - headerHeight);
			
			function scrollBg()
      {
  				current += step;
  				if (current == restartPosition){
  					current = 0;
  				}
  				$('#header').css("background-position","0 "+current+"px");
			}

			var init = setInterval("scrollBg()", scrollSpeed);