§ 71.042 OVERTAKING VEHICLES ON THE LEFT.
   The following rules govern the overtaking and passing of vehicles proceeding in the same direction, subject to those limitations, exceptions, and special rules otherwise stated in this chapter:
   (A)   The driver of a vehicle overtaking another vehicle proceeding in the same direction shall pass to the left thereof at a safe distance, and shall not again drive to the right side of the roadway until safely clear of the overtaken vehicle. In no event shall the movement be made by driving off the pavement or the main traveled portion of the roadway.
   (B)   Except when overtaking and passing on the right is permitted, the driver of an overtaken vehicle shall give way to the right in favor of the overtaking vehicle on audible signal, and shall not increase the speed of his vehicle until completely passed by the overtaking vehicle.
   (C)   The driver of a two-wheeled vehicle may not, in passing upon the left of any vehicle proceeding in the same direction, pass upon the right of any vehicle proceeding in the same direction unless there is an unobstructed lane of traffic available to permit the passing maneuver safely.
(ILCS Ch. 625, Act 5, § 11-703) Penalty, see § 70.99