Cold-weather biking (also referred to as winter biking, snowbiking or icebiking) is the activity of cycling in winter weather with snow, ice, and slush. As in warm months, people bike in cold-weather for several reasons. Bike commuters cycle to work for exercise, to reduce their carbon footprint, or to save on the costs of parking, amortized car purchase (by making less frequent), car maintenance, insurance, and fuel. Recreational snow or ice-bikers include off-road bikers who ride on snowmobile trails with underinflated, fat tires and ice-bikers who use frozen streams, ponds, or rivers, or who race on iced-over lakes.
Winter roads may have less space for cars and bicycles to share, when snowbanks line the roads. To maintain control of a bike on icy roads, cyclists need a different riding style than they would use in summer. Bikers tend to ride more slowly and cautiously, be more upright on turns, and avoid using the front brake on icy roads, because front braking can lead to skidding and crashing.
Cold-weather bikers usually wear several layers of protective clothing to keep warm, including insulating layers such as merino wool and wind- and water-resistant outer shell layers. Protecting the extremities (feet and hands) from the potentially frostbite-causing effects of subzero windchill is a particular challenge, as is keeping wind off the face.
Some cold-weather bikers use special bike gear to deal with the inclement weather, such as metal-studded tires to improve traction, enclosed chain cases and internal hub gears to shield the drive train from ice, and hub brakes or enclosed drum brakes, which can operate even when the wheel rims are caked in ice. Bikers may have to clean caked-on ice and snow from brake pads, rims, and derailleur cassettes during and after a ride, to remove corrosive road salt and metal-wearing grit and sand from chains and derailleurs.
Reference: Wikipedia Snowbiking