In the Montana Rockies (where -40 is not unusual) I rode twice in December and twice in January last season, once in December (last Friday) so far this year. But these are exceptions. Climate change is real as in the past Nov.-Feb. riding was out of the question. There are certainly more hazards in the "off season" - slick de-icer (and what it does to metal), sand and sudden frost/ice in shaded canyon corners. Here's another: cagers who do not expect to see bikes on the road have put them out of their consciousness - out of mind, out of sight. As far as a "lay-up" regimen goes, use a Battery Tender and pigtail, put Seafoam in the tank, use a cover (optional). When you get that warm day, you're good to go.
By the way, the coldest temp ever recorded in the Lower Forty-Eight was at a mining camp on Rogers Pass west of Great Falls, Mont., in 1957 - minus 70 degrees. What is not known is how hard the wind was blowing that day. Talk about wind-chill! Your nostrils freeze shut if you inhale through them. Your pee crackles as it freezes before it hits the ground. As my German extraction father would have said, "That's Gott Damn cold!"