05 05 2011 Close-up of a bicycle’s back wheel on a sunlit, paved surface. The image shows the tire, spokes, and part of the rear gear mechanism casting a shadow on the ground. The background features a curb with some grass visible. 0 Close-up of a bicycle’s back wheel on a sunlit, paved surface. The image shows the tire, spokes, and part of the rear gear mechanism casting a shadow on the ground. The background features a curb with some grass visible.