var scrollSpeed = 120;
	var step = 1;
	var current = 0;
	var imageWidth = 2000;
	var headerWidth = 2000;		

	var restartPosition = -(imageWidth - headerWidth);

	function scrollBg(){
		current -= step;
		if (current == restartPosition){
			current = 0;
		}

		jQuery('html, body').css("background-position",current+"px 0");
	}

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