Texas Transportation Code - TRANSP § 551.102. General Operation

(a) A person operating a bicycle shall ride only on or astride a permanent and regular seat attached to the bicycle.

(b) A person may not use a bicycle to carry more persons than the bicycle is designed or equipped to carry.

(c) A person operating a bicycle may not use the bicycle to carry an object that prevents the person from operating the bicycle with at least one hand on the handlebars of the bicycle.

(d) A person operating a bicycle, coaster, sled, or toy vehicle or using roller skates may not attach either the person or the bicycle, coaster, sled, toy vehicle, or roller skates to a streetcar or vehicle on a roadway.