While browsing information for Russian tracks to add to the database, I stumbled on a Russian kart manufacturer. Nice looking made-for-winter kart they have!
This one’s fitted with a Rotax Max Engine. A lot of the outdoor rental tracks in Russia look like they operate year-round, changing the tyres over when the track is ice instead of asphalt.
All their other karts seemed to be rental karts with 4 stroke engines. Check out the manufacturer’s website.