Wis. Stat. § 895.049: Recovery by a person who fails to use protective headgear while operating certain motor vehicles.

Notwithstanding s. 895.045, failure by a person who operates or is a passenger on a utility terrain vehicle, as defined in s. 23.33 (1) (ng), a motorcycle, as defined in s. 340.01 (32), an all-terrain vehicle, as defined in s. 340.01 (2g), or a snowmobile, as defined in s. 340.01 (58a), on or off a highway, to use protective headgear shall not reduce recovery for injuries or damages by the person or the person’s legal representative in any civil action. This section does not apply to any person required to wear protective headgear under s. 23.33 (3g), 23.335 (8) (a) or (b), or 347.485 (1).