Directions and online video say to use the jetting for the coldest temperatures you would typically run into and it will lean it out from there. That way it will be rich enough should you ride in that temp. We ride up lake of the woods at least once a winter and it isnt uncommon for it to be -25 degrees when leaving in the morning for ice fishing. I found the service book for this sled. Looks like 600-1200 ft; 320 pto/310 mag #3 needle slot for -10 to -30 degrees. I might richen up one size just to be safe.
