Wash it with warm water and dishwashing liquid after every ride--just a drop of diswashing detergent, fill with warm water, cap, shake shake shake. Squirt some suds out of the spout to wash the outside of the bottle, squirt some soapy water out, and rinse all parts well. Air dry. If you store a bottle wet, it will provide mold with an ideal place to grow.
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You're east of East St. Louis
And the wind is making speeches.