In both Missouri and Illinois, bicyclists are considered vehicle operators. You have a right to ride your bicycle on the road, and you have the responsibility to obey the rules of the road. Municipalities sometimes have ordinances governing bicycling within city limits.
City of St. Louis bicycle ordinances are posted here:
http://www.slpl.lib.mo.us/cco/code/data/t1736.htm
Missouri:
On July 12, 2005, SB 372 was signed by the Governor. SB 372, sponsored by Sen. Kevin Engler (R-Farmington), provides for various measures relating to bicycle safety and the duties owed to bicyclists by motorists. Some of the provisions in the bill, which resulted from a collaboration of the Missouri Bicycle Federation and the St. Louis Regional Bicycle Federation, include the following.
DESIGNATED BICYCLE LANES - This act prohibits blocking or obstructing
a designated bicycle lane with a parked or standing motor vehicle or other
stationary object. The act establishes standards for motorists crossing
bicycle lanes. The act defines a designated bicycle lane as a portion of
the roadway or highway, which has been designated by the governing body
having jurisdiction over the roadway by striping, signing and pavement
markings for the preferential or exclusive use of bicycles (Section
300.330).
AVOIDING COLLISION WITH A BICYCLIST OR PEDESTRIAN - Under this act,
when passing a bicyclist, a motorist is required to leave a safe distance
between the motor vehicle and the bicycle (Section 300.411 and Section
304.678).
DEFINITION OF BICYCLE - This act modifies the definition of bicycle to
include vehicles propelled by human power having two parallel wheels and
one forward or rear wheel, all of which are more than 14 inches in diameter
(Section 307.180).
RIDING ON SHOULDERS - This act provides that bicycles operating at
less than the posted speed limit or slower than the flow of traffic may be
operated on the shoulder adjacent to the roadway (Section 307.191).
BIKE HAND SIGNALS - This act provides that a bike rider shall signal
in the same manner as other vehicles except that the rider does not have to
continuously signal by hand and arm if the hand is needed for the control
or operation of the bicycle (section 307.192).
Missouri statutes
Rights and duties of bicycle and motorized bicycle riders.
307.188. Every person riding a bicycle or motorized bicycle upon a street or highway shall be granted all of the rights and shall be subject to all of the duties applicable to the driver of a vehicle as provided by chapter 304, RSMo, except as to special regulations in sections 307.180 to 307.193 and except as to those provisions of chapter 304, RSMo, which by their nature can have no application.
Riding to right, required for bicycles and motorized bicycles.
307.190. Every person operating a bicycle or motorized bicycle at less than the posted speed or slower than the flow of traffic upon a street or highway shall ride as near to the right side of the roadway as safe, exercising due care when passing a standing vehicle or one proceeding in the same direction,
EXCEPT
when making a left turn, when avoiding hazardous conditions, when the lane is too narrow to share with another vehicle, or when on a one-way street. Bicyclists may ride abreast when not impeding other vehicles.
Riding bicycle on sidewalks, limitations--motorized bicycles prohibited.
300.347. 1. No person shall ride a bicycle upon a sidewalk within a business district.
2. 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.
3. No person shall ride a motorized bicycle upon a sidewalk.
Riding bicycles, sleds, roller skates, by attaching to another vehicle, prohibited.
300.350. No person riding upon any bicycle, motorized bicycle, coaster, roller skates, sled or toy vehicle shall attach the same or himself to any vehicle upon a roadway.
Bicycle and motorized bicycle, defined
307.180. As used in sections 307.180 to 307.193:
(1) The word "bicycle" shall mean every vehicle propelled solely by human power upon which any person may ride, having two tandem wheels, except scooters and similar devices;
(2) The term "motorized bicycle" shall mean any two- or three-wheeled device having an automatic transmission and a motor with a cylinder capacity of not more than fifty cubic centimeters, which produces less than three gross brake horsepower, and is capable of propelling the device at a maximum speed of not more than thirty miles per hour on level ground. A motorized bicycle shall be considered a motor vehicle for purposes of any homeowners' or renters' insurance policy.
Brakes required
307.183. Every bicycle and motorized bicycle shall be equipped with a brake or brakes which will enable its driver to stop the bicycle or motorized bicycle within twenty-five feet from a speed of ten miles per hour on dry, level, clean pavement.
Lights and reflectors, when required--standards to be met
307.185. Every bicycle and motorized bicycle when in use on a street or highway during the period from one-half hour after sunset to one-half hour before sunrise shall be equipped with the following:
(1) A front-facing lamp on the front or carried by the rider which shall emit a white light visible at night under normal atmospheric conditions on a straight, level, unlighted roadway at five hundred feet;
(2) A rear-facing red reflector, at least two square inches in reflective surface area, or a rear-facing red lamp, on the rear which shall be visible at night under normal atmospheric conditions on a straight, level, unlighted roadway when viewed by a vehicle driver under the lower beams of vehicle headlights at six hundred feet;
(3) Reflective material and/or lights on any part of the bicyclist's pedals, crank arms, shoes or lower leg, visible from the front and the rear at night under normal atmospheric conditions on a straight, level, unlighted roadway when viewed by a vehicle driver under the lawful lower beams of vehicle headlights at two hundred feet; and
(4) Reflective material and/or lights visible on each side of the bicycle or bicyclist and visible at night under normal atmospheric conditions on a straight, level, unlighted roadway when viewed by a vehicle driver under the lawful lower beams of vehicle headlights at three hundred feet. The provisions of this subdivision shall not apply to motorized bicycles which comply with National Highway Traffic and Safety Administration regulations relating to reflectors on motorized bicycles.
Penalty for violation
307.193. Any person seventeen years of age or older who violates any provision of sections 307.180 to 307.193 is guilty of an infraction and, upon conviction thereof, shall be punished by a fine of not less than five dollars nor more than twenty-five dollars. Such an infraction does not constitute a crime and conviction shall not give rise to any disability or legal disadvantage based on conviction of a criminal offense. If any person under seventeen years of age violates any provision of sections 307.180 to 307.193 in the presence of a peace officer possessing the duty and power of arrest for violation of the general criminal laws of the state or for violation of ordinances of counties or municipalities of the state, said officer may impound the bicycle or motorized bicycle involved for a period not to exceed five days upon issuance of a receipt to the child riding it or to its owner.
Illinois statutes say the same thing!
Missouri Statute
Section 300.340. Opening and closing vehicle doors.
No person shall open the door of a motor vehicle on the side available to
moving traffic unless and until it is reasonably safe to do so, nor shall any person leave a door open on the side of a motor vehicle available to moving traffic for a period of time longer than necessary to load or unload passengers.