Yamaha BRUIN 350 YFM350AS Owner's Manual page 360

5. Tie a plastic bag over the exhaust pipe outlet
to prevent moisture from entering.
6. If storing in a humid or salt-air atmosphere,
coat all exposed metal surfaces with a light
film of oil. Do not apply oil to any rubber parts
or the seat cover.
7. Remove the battery and charge it. Store it in
a dry place and recharge it once a month. Do
not store the battery in an excessively warm
or cold place (less than 0 °C or more than
30 °C).
NOTE:
Make any necessary repairs before storing the
machine.
9-9