Here are some tips of winterizing your motorcycle.
Wash the bike. Dirt and grime can corrode your paint if they sit on your bike all winter. Give your bike a thorough wash to get it as clean as possible. Wax the bike to create a layer of protection from moisture, then treat the saddle with a leather conditioner to keep it from cracking in the cold.
Grab the WD-40. Just as you wax the bodywork to keep it protected from the moisture of winter, a light spray of WD-40 will repel water and keep other exposed metal work from succumbing to corrosion. Key areas to spray are the engine, the frame and tailpipes.
Change your fluids. When fuel sits for too long in a tank, it begins to oxidize, leaving gummy deposits and layers of varnish that can clog up the fuel system. Take the bike out for one last ride, then stop at a station to top off the tank. The ride back home will get the stabilized fuel mixture running through the entire system. When you get back home, replace the oil and filter on the bike as well — old oil can cause corrosion inside your bike’s engine. Additionally, if your bike is carbureted, you’ll want to drain fuel from the float bowls. Finally, if your bike is liquid cooled, change out the coolant.
Tend to the Battery. Batteries, sitting unused in the cold, have a tendency to self-discharge. To keep your battery charged and ready for the next riding season, be sure to install a battery tender. Battery tenders keep the battery at a consistent power level while your bike sits. Before setting it up, check the terminals to make sure they’re clean and, if needed, treat them with dielectric grease.
Protect your tires. To keep the bike’s tires from developing flat spots, it’s ideal to keep both wheels up on stands during the winter. If you don’t have stands, try to roll your motorcycle once every couple of weeks to keep the tires from sitting in one spot. Also, if you have to leave the motorcycle sitting on concrete, place plywood or carpet between the tires and the garage floor to keep moisture from seeping into them.
[Source : http://gearpatrol.com/2016/09/05/how-to-winterize-your-motorcycle/]