§ 73.046 RIDING ON MOTORCYCLES.
   (A)   A person operating a motorcycle shall ride only upon the permanent and regular seat attached thereto, and the operator shall not carry any other person nor shall any other person ride on a motorcycle unless the motorcycle is designed to carry more than one person, in which event a passenger may ride upon the permanent and regular seat if designed for two persons, or upon another seat firmly attached to the motorcycle at the rear or side of the operator.
   (B)   A person shall ride upon a motorcycle only while sitting astride the seat, facing forward, with one leg on each side of the motorcycle.
   (C)   No person shall operate any motorcycle with handlebars higher than the height of the shoulders of the operator when the operator is seated in the normal driving position astride that portion of the seat or saddle occupied by the operator.
(ILCS Ch. 625, Act 5, § 11-1403) Penalty, see § 70.99