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Discussion Starter #1
Wondering if it would be a problem if hooking up an external automotive 12v battery through the accessory outlet would cause any issues to my K1200lt. Keep bike at a storage unit with no ac outlets to plug a charger into. Trying to eliminate what little drain is on the bikes internal battery. Have an extra car battery on hand that is not being used.

Thanks
 

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why not just remove battery and store it at home?

another option use a deep cycle battery with a converter to power battery tender. I am just not sure how long battery would last.

just my .02
 

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Wrencher Extraordinaire
2005 K1200LT
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I stored a Suzuki GT-750 for 11 months at a time during Navy deployments. Charged the battery drove it to the storage site and put in Stabil and ran the gas out of the carbs and disconnected the battery negative terminal. She always fired right up when I took her out of storage. Most batteries will not self discharge.

You will loose some programming of your radio and the alarm has an internal battery that may go flat. Then it may fail over to the armed mode when you try to start her again. You may be better off doing what you suggested. Average fully off draw by an LT is about 5 ma so a fully charged car battery may make it for a few months.
 

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Discussion Starter #4
Trying not to disconnect internal battery. Just wanting to make certain no damage will occur if plugged in via the accessory port.
 

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cbpip said:
Trying not to disconnect internal battery. Just wanting to make certain no damage will occur if plugged in via the accessory port.
Why don't you want to disconnect the bike battery?

I don't see any reason that you could cause any harm connecting the auto battery. However, the self-discharge of auto battery is probably greater than the draw from the LT!

Lead acid batteries have discharge rates of 2-5% per month. The low end is for AGM batteries and the high end for standard flooded cell lead acid. So, after 6 months you will be down to about 75% of full charge with a flooded cell and after 12 months you will be at about 55% of full charge. This is likely still plenty to start the bike using the car battery, but may not be enough on the bike battery alone.
 

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Discussion Starter #6
Trying to minumize the amount of time to get on the bike and be able to putt versus hooking up a battery everytime. Also trying to keep my internal battery at a higher state thank just being left unattended . Not sure if the larger automotive battery will draw down the internal battery to its state to balance itself now that I'm thinking about it? If the larger battery starts out fully charged this should not happpen I think. I would be peaking up the auto battery from time to time.
 

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I would not connect another battery by the bike battery. If there might be any difference in the condition of the batteries you end up feeding either the external battery or the internal/bike one uncontrolled way and uncontrolled AMPs. Why not use quality battery tender to maintain your battery if you do not want to disconnect the bike one. I have my bike connected to battery tender whenever it is not on the road and here in Finland during winter time it means about 6 months in a row. Never had problems with the battery for that reason.
 

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cbpip said:
Wondering if it would be a problem if hooking up an external automotive 12v battery through the accessory outlet would cause any issues to my K1200lt. Keep bike at a storage unit with no ac outlets to plug a charger into. Trying to eliminate what little drain is on the bikes internal battery. Have an extra car battery on hand that is not being used.

Thanks
Is there a light bulb in the storage area? If so screw in an adaptor and plug in the tender.

Robert
 

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Discussion Starter #10
There is a light bulb but they put them on a 30 min timer that controls multiple units outside of the unit itself otherwise I would do just that and put something on the timer to stop the count down. Thought about doing that anyway.
 

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cbpip said:
There is a light bulb but they put them on a 30 min timer that controls multiple units outside of the unit itself otherwise I would do just that and put something on the timer to stop the count down. Thought about doing that anyway.
If you have power to the unit, it would not be hard to add an outlet before the timer. I would want switchable light in a storage unit anyway, as long as power is there.
 

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BEST CASE, assuming bike battery and car battery are both in prime condition, they will both discharge at about the same rate, and the power draw from the bike will have much less impact on the pair than on the bike alone.

Real life: is your "spare" car battery really better than the bike battery? The battery with the higher self-discharge rate will drain the other battery, probably much faster than the radio and computer will.

I don't think this is likely to actually help you, and may hurt you...
 

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I'll second the solar charger option. Low current and "free" power. Just route it so the panel is up high away from sticky fingers.

I would not recommend hooking one battery to another. Remember a battery has alot of current available. If there is a problem with either battery (internal short), the other battery will feed the short with abandon (yes, the fusing through the accessory outlet circuit should protect the system, but a "smart-short" could sit just below the fuse limit).
 

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cbpip said:
There is a light bulb but they put them on a 30 min timer that controls multiple units outside of the unit itself otherwise I would do just that and put something on the timer to stop the count down. Thought about doing that anyway.
If it is a manual twist type timer find a stick and cut it to the right length to keep the knob from turning. Won't hurt a thing and you don't have to modify someone else's wiring. Just unscrew the bulb or install an adapter with a pull chain.

Robert
 

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Scouter-50 said:
If it is a manual twist type timer find a stick and cut it to the right length to keep the knob from turning. Won't hurt a thing and you don't have to modify someone else's wiring. Just unscrew the bulb or install an adapter with a pull chain.

Robert
Sounds like theft to me.
 
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