On Sept 18, 2015, a Norwegian man, Morten Blien, age-30, drove his Polaris RMK-800 snowmobile for a 212-km ride, or 131-miles, down the Tona River in Norway. Listen to the engine, and it sounds to be a 2-stroke engine ...... it is a 2-stroke? Go Morten ....... go..... way-to-go ..... Morten!
https://vimeo.com/139846766
"There is some question of whether snowmobiling on the Tona River is legal, however. While the municipalities of Tona and Karasjok both approved it, the county governor of Finnmark argues that they do not have this right as it does not follow the laws for small boats."
Snowmobile skimming is not legal in New Hampshire, Maine, and Minnesota according to
https://en.wikipedia.org/wiki/Snowmobile_skipping