Battery Chargers

[wilmas2cool]

On our '83 GS1100E I was hooking up a Schumaker self regulating 1.5 amp battery charger for several days on a six month old battery and when I went to ride the battery seamed low on starting power. The engine turned over and cranked up but kind of slow. The bike ran good. Later I started unhooking the positive battery cable and left the charger on for a few days and when I reattached the battery cable I had a lot more starting power. The starter turned over really fast and the engine cranked up instantly like a new bike. My question is are the older bike RR's not compatible with self regulating chargers ? Does the RR bleed off power from the battery during charging ? The exact same thing happens on our 1980 Goldwing and our neighbor's V-Max. Thanks in advance.

[tom203]

You shouldn't really have to charge your battery this much. Once charged- whether from riding or a battery charger- your battery should be able to sit at least two weeks with plenty of juice waiting.
As for your "self-regulating" charger, I'm skeptical- if it's pumping even .5 amp into your battery for days, your battery will not be happy for long. The new battery maintainer chargers drop the charging rate to very small levels once the battery is fully charged and so they can be left on. But you shouldn't need to do this- are you sure your bike's charging system is working correctly?
If a diode in the r/r was bad, it could possibly "leak", but this gets back to the question of your bike's charging system.

[wilmas2cool]

Thanks for your reply tom203. The battery charger is an automatic battery maintainer type like a Battery Tender made for motorcycles. We started using it because we have 4 old bikes from the 80's that are in good shape but our work schedule (self employed) means that the bikes might sit from days to weeks between rides. The 83' GS1100E got a new RR and stator and the charging system is testing with in specs. At times I can ride it once a week and the battery stays strong. It starts getting weaker when it has to sit. The thing I have noticed is I can park it with a strong battery, put the charger on with the battery positive cable still attached, come back four days later to crank it and it cranks / starts really slow and weak. If I disconnect the positive cable, put the charger on, come back four days later the battery is fully charged and it starts like a new bike. My neighbor has the same results with his Battery Tender brand. I was wondering if anyone else had experienced this. Like most bikes, the more often I ride the better everything works. Also the batteries are the cheap ones from Autozone. I did a couple of business trips to the Maine coast. Best lobster ! Really enjoyed it. We are looking forward to a return on the bikes.

[fastpakr]

It sounds to me like you have a constant drain on your electrical system.

[bwringer]

Not sure this is your problem, but... regulator/rectifiers with a sense wire (like the common Honda R/R upgrade) will slowly drain the battery if the sense wire is left hooked up.

The sense wire is supposed to be connected to a SWITCHED positive -- a wire that only gets +12VDC when the key is on.

These Honda R/Rs usually have three yellow stator wires, a red positive, a green ground, and a thinner black sense wire. (Sometimes they have two red wires and two green wires.)

[wilmas2cool]

Thanks for the input. This one got the Electrosport RR and stator. I'll check my charging numbers again. I've got it back on the charger with the positive battery cable attached and will check it again this weekend.

[tom203]

When you can, try this; disconnect the positive battery cable, use your multimeter in amp mode ( say .2 amp range )- put one probe on battery terminal and other probe on the disconnected battery cable. There should be no current flowing with key in off position.