I've got an electrical problem

On a Honda GL1800.
I bought the bike used in 2006. It arrived with a bad cell in the battery. I muttered, and replaced it, even though the date on the battery was only 6 months earlier. Had a bad cell, wouldn't charge, only put out 10v with any load.
I broke my leg in Sept, so the bike sat in the garage for 3 months. Went to start it, no go. Hooked up the charger.. no charge. Bad cell.

What I think is happening is: even when turned off, there is still a drain on the battery, and one of the cells is being over discharged, and getting plated (I believe with lead sulfate).
Questions:
1) anyone else hit this
2) any cure other than a new battery (plus a tender of course)  

I have a 2001 GL1800 and after 8 years the battery gave up, no supprise. Bought a new one but it went total flat when I was away for three months, would not take a charge. Replaced under warenty and that one went flat after 2 days.Recharged the battery. Did a search for parasidic current draw and had over 1 amp draw, should be less than 5 milli amps. Found it to be the radio. The standby power which comes of fuse 22 (20 Amp)was going to ground through the radio draining the battery. Suggest after you get a new battery, you install with the negative terminal disconected and put an amp meter, posative lead of amp meter on negative terminal of battery and negative lead of amp meter on the disconnected negative battery wire. See what amperage is being drawn. All this with the key off. Remember less than 5 milli amps is normal. If draw greater than 5 milli amps remove the 20 amp fuse #22 and see if the current draw drops to zero and that would indicate the radio to be the problem. Expensive to replace $1300 to $1800. Currently looking for a better buy on one.

Good luck
JFR  

Was able to get the radio unit repaired for $105 at Custone Electromotive in Whitby Ontario, Canada 905-668-2664. It seems the IC (intigrated chip) in the radio fails to ground causing the drain on the battery.

JFR  

Thanks for the info.