For this last question, the focus is going to be kept on carbon. One of the other advantages to the material, which was not touched on earlier, is that it is remarkably easy to care for as it is fairly resistant to damage. What is even nicer is to clean and maintain it, you really are okay with resorting to simple soap and water. While you should keep the soap mild, this is going to be efficient nine times out of 10.
But, it is also worth noting that carbon does hold up well to other solvents. But, many experts will tell you that it is simple and good practice to resort to mild soap and water. In addition, this is only going to be necessary every so often (unless you enjoy trail riding and your bars are always exposed to dirt and grime).