373.08 RIDING ON SIDEWALKS.
   (a)    No person shall ride a bicycle upon a sidewalk within a business district.
   (b)    No person fifteen or more years of age shall ride a bicycle upon any sidewalk in any district.
   (c)    Whenever any person is riding a bicycle upon a sidewalk, such person shall yield the right of way to any pedestrian and shall give audible signal before overtaking and passing such pedestrian.
   (d)    No person shall ride a skateboard or platform with wheels attached or propel themselves with roller skates upon any sidewalk within the Central Business District.