Section 343.45 - Permitting unauthorized person to drive(1) No person shall cause or knowingly permit the person's child or ward under 18 years of age to operate a motor vehicle upon any highway in violation of this chapter or when such minor is not authorized under this chapter to operate a motor vehicle.(2) No person shall authorize or knowingly permit a motor vehicle owned by the person or under the person's control to be operated upon any highway in violation of this chapter or by a person who is not authorized under this chapter to operate a motor vehicle. No dealer as defined in s. 340.01(11) (intro.) but including the persons specified in s. 340.01(11) (a), (b), (c) and (d) , shall permit any person to operate any motor vehicle owned by the dealer or in the dealer's possession or control on a trial run unless the dealer has been shown the person's valid operator's license, issued by this state or other jurisdiction, before permitting the trial run.(3) Except as another penalty is provided by s. 343.245(4) (b) , any person violating this section may be required to forfeit not more than $100.1971 c. 278; 1989 a. 105, 359. A parent's unrestricted entrustment of a motorcycle to minor child in violation of this section constituted negligence per se. Kempf v. Boehrig, 95 Wis. 2d 435, 290 N.W.2d 563 (Ct. App. 1980).