Cold weather motorcycle riding is doable and enjoyable if you and your bike are properly equipped.
My first cold weather trip took place in December of 2012. The ride was to be from Iowa City, IA to Sedona, AZ. A snow storm in Iowa changed my plan. I would have to haul the bike South to begin the trip. I loaded up the bike and hauled it to Jefferson City, MO. This got me South of the snow-covered roads. I had very little experience with cold weather riding and thought once I got South far enough the cold wouldn't be an issue. Wrong. I found out the Southern US does have winter!
I had done some research online and went for some short cold rides close to home to test gear that I had purchased. I had also done a lot of snowmobile riding as a kid. I would find out that riding a motorcycle at sustained highway speeds is colder than trail riding a snowmobile the woods.
My ride was (and still is) a 2009 Harley Davidson Street Glide. I added a taller windshield, soft lowers, and a 12 volt temperature controller for my heated riding gear.
The clothing I wore on the coldest days was a short sleeve t-shirt, long sleeve wool shirt, heated jacket liner, leather jacket, rain jacket, jeans, leather chaps, waterproof bib overalls, riding boots, heated gloves, balaclava and full face helmet. The rain jacket and water proof bibs helped to block the wind and hold body heat in.
The only problems I had where my glasses fogging inside my helmet and my feet getting cold. These issues only came up on the coldest days. (30 to 40 degrees F). The fogging problem I solved by switching to contacts. For my feet I used chemical hand/foot warmers in my boots. I have since purchased a helmet with better ventilation that helps with the fogging problem. There are heated socks available to connect to my 12 volt temperature controller but the hand/foot warmers are cheap and work well.
There are many products available for riding in the cold but the ones I think are the most important are a good fairing with windshield, a heated jacket liner and a good full face helmet. The windshield keeps the cold wind from hitting you directly. The heated jacket keeps your core warm and helps keep the rest of your body warm. The helmet also helps block the wind and keep body heat in.
Cold weather riding is a good way to extend the riding season and to add some variety to your riding. It is completely different from riding out of the garage in a t-shirt when it's 85 degrees F. It takes more preparation and planning but, if you love to ride, it's worth it.