Results for: so I have a motorcycle and use the Optimate1 battery tender. One day while using the tender I left and came back 6 hours later to find the Optimate still charging my battery. The battery was very hot so I unplugged right away. I let the battery cool off and the next day I started the bike and the battery was fine. I used my Volt meter and the battery was holding a charge of 14.5 Volts and when I started the bike it did not drop below 9 Volts, and when the bike was running it puts out 16 Volts so I know the battery is being charged. Since the Optimate overcharged my battery it won't go into the green maintain mode - It just keeps charging.

I took the Optimate back to the shop thinking it was the charger, but they hooked it up to 2 batteries and it went to maintain within a minute like it used to for me before this happened. Why won't the Optimate go to maintain when the battery is fully charged when I test it with my Volt meter? Is the battery bad possibly? And if so why does it give a full charge and still fire up the bike fine? I'm not sure what to do?

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    Have you tried it again to see if it would go into maintenance mode since then? I was reading that the Optimate1 will try to charge to 14.4vdc and then go into maintenance mode. It seems to me the charging system on your bike is running a bit high, as the max I would expect to see out of it would be around ~14.1vdc. Jul 29, 2014 at 22:44

1 Answer 1


The Optimate is probably looking for a decrease in charging current to trigger the transition to maintenance mode. A battery in good condition should start accepting less current as it nears a fully charged state. It sounds like this wasn't happening with your battery. It may be that the battery is nearing the end of its life.

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