When you drive over certain surfaces, such as grooved or rutted pavement or metal bridge gratings, you may feel as though you are losing control of your motorcycle or moped. This effect is greater on smaller vehicles than it is on larger ones; the smaller your vehicle the larger the effect. Avoid overreacting. Keep a gentle but firm grip on the handlebars and drive as smoothly as you can, choosing the best route possible until you get back on a good surface.