I missed my first ride of the year, the Polar Bear ride with the CMA and Southern Cruisers, due to my spark plug issue.
Winterizing a motorcycle:
Windscreen - a must.
Polar Hands,used by snowmobile riders for years - a very nice addition.
Heat lamp to clamp on your lower frame to warm the engine enough to start at 20°F - another must have.

Ride Safe, Dennis Triumph, it's how I live and what I ride.