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Trickle charger options

For my money the best answer is a high amp hour RV battery in parallel with the bike battery. Absent the wisdom of the electrical engineer guru types I invited in post # 7 I predict 3 months of no problems. Then charge the RV battery and repeat.
 
For my money the best answer is a high amp hour RV battery in parallel with the bike battery. Absent the wisdom of the electrical engineer guru types I invited in post # 7 I predict 3 months of no problems. Then charge the RV battery and repeat.

Hi Paul,
If you can accept a 10% drawdown of the big battery, and there are no added parasitic drains other than an Oilhead’s usual 2.5 mIlliamperes, then it should be good for half a year. That doesn’t take into account the self-discharge rate of the big battery though, which could be significant.
 
Hi Paul,
If you can accept a 10% drawdown of the big battery, and there are no added parasitic drains other than an Oilhead’s usual 2.5 mIlliamperes, then it should be good for half a year. That doesn’t take into account the self-discharge rate of the big battery though, which could be significant.

Thanks. I think 2 to 3 months works, then.
 
Paul,

Here is what I found:

“The rate of self-discharge for lead acid batteries depends on the storage or operating temperature. At a temperature of 80 degrees F. a lead acid battery will self-discharge at a rate of approximately 4% a week. A battery with a 125-amp hour rating would self-discharge at a rate of approximately five amps per week.”

This rate is higher than an odyssey pc680 and at four percent per week, it would not be a good way to keep a bike’s battery alive.

If one doesn’t have AC for a maintenance charger, best to remove the battery or maybe rig a solar charger.
 
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