Mont. Code Ann. § 23-2-654

23-2-654 . Snowmobiler's assumption of responsibility -- duties. (1) A snowmobiler shall operate a snowmobile at all times in a manner that avoids injury to self and others and must be aware of the inherent risks in the sport of snowmobiling.

(2) A snowmobiler shall:

(a) know the range of the snowmobiler's ability and snowmobile safely within the limits of that ability and the snowmobiler's equipment so as to negotiate any section of terrain or snowmobile trail safely and without injury or damage. A snowmobiler must be aware that the snowmobiler's ability may vary because of terrain or trail changes caused by weather, grooming changes, or snowmobile use.

(b) maintain control of speed and course at all times while snowmobiling so as to prevent injury to self and others;

(c) heed all posted warnings; and

(d) refrain from acting in a manner that may cause or contribute to the injury of anyone.

(3) A snowmobiler shall accept all legal responsibility for injury or damage of any kind to the extent that the injury or damage results from risks inherent in the sport of snowmobiling. Risks inherent in the sport of snowmobiling are:

(a) variations in terrain, including surface or subsurface snow or ice conditions naturally occurring or resulting from weather changes, snowmobile use, or grooming or snowmaking operations;

(b) bare spots or thin snow cover caused by limited snowfall, melting, wind erosion, snowmobile action, grooming, or unconsolidated base;

(c) rocks, trees, or other forms of forest growth or debris;

(d) clearly visible or plainly marked improvements or trail maintenance equipment; and

(e) avalanches.

(4) The provisions of this section do not affect a products liability cause of action based upon the design or manufacture of snowmobile equipment or products or safety equipment used incidental to the operation of a snowmobile.