N.Y. Veh. & Traf. Law § 1251

§ 1251. Riding on motorcycles. (a) A person operating a motorcycle\nshall ride only upon the permanent and regular seat attached thereto,\nand such operator shall not carry any other person nor shall any other\nperson ride on a motorcycle unless such motorcycle is designed to carry\nmore than one person, in which event a passenger may ride upon the\npermanent and regular seat if designed for two persons, or upon another\nseat firmly attached to the motorcycle at the rear or side of the\noperator.\n (b) A person shall ride upon a motorcycle only while sitting astride\nthe seat, facing forward, with one leg on each side of the motorcycle,\nunless said person is seated in a sidecar affixed to said motorcycle.\n (c) No person shall operate a motorcycle while carrying any package,\nbundle or other article which prevents him from keeping both hands on\nthe handlebars.\n (d) No operator shall carry any person, nor shall any person ride, in\na position that will interfere with the operation or control of the\nmotorcycle or the view of the operator.\n