Knurling is widely used in many industries for a number of reasons. Ordinarily, you knurl a piece of metal so it can't slip in its mounting clamp. In the motorcycle world, knurling handlebars for the riser is most common. When you to change your handlebars, the new bars may not be knurled. As a safety precaution, you will want to do this so that the bars don't move while in the risers. Sometimes the area where the grips go on the bars is also knurled to help keep them from sliding off. We stopped at V-Twin City and asked Scruffy to show us a couple ways that handlebars can be knurled.