Just make sure you are connecting to the correct POS(+) and NEG(-)- terminals. Can't always go by the color of the wires. Find the word POS and NEG or the symbols + and - on the battery case.
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You should also learn how to check your battery fluids and do this every couple of weeks to be sure your small trickle charger is not boiling out your battery fluids...
I would also pick up a inexpensive mulitmeter and keep tabs on your battery DC Voltages. A fully charged battery will read 12.6-7VDC across the battery terminals. You do not want the battery levels to EVER get below 12.0VDC for an extended time otherwise you will start doing harm to your batteries.
Roy Ken
