Welcome to the forum.When you dropped the bike,it flooded the engine making it difficult to start.That's why when you left it setting for a while it started.You don't need to remove the battery to charge it.Just be sure you hook the red (+) from the charger to the red (+) on the battery and the same for the black (-).charge at no more than 2 amps.Once you charge the battery,the bike should start.If you have more issues,we can address them than,so as not to confuse you.Good luck.
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