id second the aluminum foil on the upper cylinder . it will help in really cold weatherespecially if you do a lot of idle/approaches etc.. keep the batteries & plane reasonably warm until ready to fly.using mostly synthetic will help as castor really gets congealed in cold weather.you may want to check out getting some large sheets of heavy clear plastic at hardware store to put up around the lean to or at least a couple tall posts with plastic as a wind break. even a light breeze in winter is very chilly.