Is it illegal to ride your bike down a one-way street against the flow of traffic? Is it illegal to ride your bike down the sidewalk of a one-way street against the flow of traffic?
Whether the roadway is one-way or not, when in the roadway, a cyclist has the same rights and duties as other drivers and must ride in the same direction.
When on the sidewalk or crosswalk, a cyclist has the rights and duties of a pedestrian and may ride in either direction.
See the posts on “Sidewalks and Crosswalks” and “Rights and Duties”.