I've had these, good results:
Lifetime Warranty professional grade Indoor/Outdoor gray motorcycle Cover. Fade Resistant to last forever. UV & Water resistant- Fast, Free Shipping!
dowcopowersports.com
BUT, be aware, dust (yes, fine dirt) blows around on those cold dry days.
It collects up under the cover. When the wind blows, then the cover goes against things and sandpapers them.
Also, mice, chipmunks, etc will get in there and eat/piss/shit on/in things. Stuff steel wool in your exhausts, then cover the end with plastic and electrical tape.
Parked on a paved/concrete surface? If not, get a full 4x8 sheet of plywood under it.
A splash of 2-stroke oil in the gas tank (along with your Sta-Bil) ensures no rust will form.
Long-lasting metal protector that inhibits rust, corrosion, and safeguards metal surfaces in industrial, marine, automotive, and construction environments.
zep.com
Single cans available at hardware stores. Spray it on engine, trans, forks, pipes, etc.
Works great.
Wipes off easily.