Last winter I did an experiment. Not really on purpose, mostly just by being lazy and dumb. I had 3 motorcycles in my garage and I didn't trickle charge the batteries on any of them. I had to buy 3 new batteries in the spring.
Not charging your battery does more than make it not charged. It's probably bad.
If you charge your battery, you may get a good voltage reading from it with a multimeter, but as soon as you crank the engine, I bet it drops way down. You should try that - crank it with the voltmeter connected. If it drops way below 10V, you have a bad battery.
If you bought a new battery and need to fill it with acid, make sure you follow the instructions. You have to wait a bit, then charge it for a long time. I have a video about that here:
02-22-2018, 05:43 AM
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