My battery let me down this morning. First day this winter that I couldn't ride to work. Temperature was 17F; last year the OEM battery would fail at 12F. I have not done the negative lead upgrade but today I did order this:
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This is the Optima equivalent for a motorcycle battery at 310 CCA. For tonight, I put the charger on the battery and a drop light under the cover. Hopefully this will keep everything warm enough to start in the morning. Weather guessers tell me it will be 12F when I head out. The new battery should be here in a few days.