I jump up 2 sizes on the main jet for temps in the 50's to 30's degrees, < under that I ride the couch
adjust your airscrew in a little too so it idles good
One jet size for every 20* colder from perfect summer jetting.
Be aware you can cold seize if you run hard like ice racing.
Think wind chill. Some cardboard to keep the air from directly hitting cylinder/head.