Under Iowa law, bicycles have a right to use Iowa's roads. Under Iowa law, bicyclists must follow the same rules of the road as motorists.
SAFETY TIPS FOR MOTORISTS SAFETY TIPS FOR BICYCLISTS
DO NOT HONK YOUR HORN AT BICYCLISTS, They may be startled and lose control.
USE EXTRA CAUTION WHEN PASSING BICYCLES, Move entirely into the left lane; on a two-lane road, don't pass a bicycle if oncoming traffic is near.
BICYCLISTS MIGHT SWERVE TO AVOID ROAD HAZARDS, Common road hazards for bicyclists are potholes, debris, drainage grates, railroad tracks, and narrow bridges.
BE CAREFUL WHEN OPENING YOUR VEHICLE DOOR, Road widths often force bicyclists to ride close to parked vehicles where they may be injured by an opening door.
WHEN IN DOUBT, YIELD TO BICYCLES