Battery problems -- checking the charging system

[codynotes]

Aloha! I have a 2004 GS500F, and I've been having some battery problems. Last week I went to start it up and nothing would happen. The starter solenoid wouldn't even buzz, and none of the instrument lights would come on. I checked the battery and it was dead (about 2 volts across the terminals). It was then that I realized that there's an accessory position on the ignition beyond the position to lock the forks. (Why you would ever want the parking lights on when the forks are locked is beyond me. Shouldn't the accessory position be between off and on?) So, my first thought after realizing this was that, although I don't remember doing so, I probably left the lights on, and the battery died.

So, I pop started the bike and rode it around for about an hour and a half to recharge the battery. After coming back, I checked the battery again and it only had about 9 volts across the terminals. The lights would come on weakly, and the starter solenoid would buzz, but wasn't getting enough current to turn the engine over. So, I figured I hadn't ridden it around enough, and the next day I rode it for another two hours. After this, the voltage across the terminals was still only about 10.1 volts, and the start solenoid still was just buzzing.

At this point I was tired of riding the bike around (especially since it stalled a few times and I had to keep getting someone to help me pop start it). So, I went to Walmart and got a 1.5 amp motorcycle trickle charger like a number of posts on the board suggested. I hooked up the battery, but after about 30 minutes the charger's 'Check Battery' light came on. The battery was only three weeks old, and it was filled properly, so I brought it back to the store. They recharged it and tested it, and they said it was in fact a bad battery. They gave me a replacement, and now the bike starts up fine. But, since I'm uncertain about whether I originally left the lights on, I'm a little suspicious whether the charging system on my bike might be messed up.

My main question is, could the charging system ruin the battery if there's something wrong with it? Could there be something wrong with it that could fry my new battery too?

I found a post on the board that describes how to check the charging system (http://gstwins.com/gsboard/index.php?topic=38480.0), but it says it's for a 1999 GS500, and the wiring on my bike seems to be a little different. Can anyone confirm whether the 2004 GS500F has a different wiring setup?

I have a manual on order so I can see a more detailed description of what to do, but I live in Hawaii so it sometimes takes mail a really long time to arrive here. I want to make sure the new battery doesn't get ruined again in the meantime.

Does anyone have any advice? Am I just paranoid?

Sorry I wrote so much, but I guess it's better to give more details than less! (Although, I guess not if no one has the patience to read the whole thing!)

(Oh, and I dropped the bike and cracked the front fairing trying to get it on the centerstand to check the wiring, so I'm continuing to be happy that I didn't buy a brand new one as my first bike.)

[asobi]

Why you would ever want the parking lights on when the forks are locked is beyond me.

Amen to that.  It happened to me too.

So, I pop started the bike and rode it around for about an hour and a half to recharge the battery. After coming back, I checked the battery again and it only had about 9 volts across the terminals. The lights would come on weakly, and the starter solenoid would buzz, but wasn't getting enough current to turn the engine over. So, I figured I hadn't ridden it around enough, and the next day I rode it for another two hours. After this, the voltage across the terminals was still only about 10.1 volts, and the start solenoid still was just buzzing.

My main question is, could the charging system ruin the battery if there's something wrong with it? Could there be something wrong with it that could fry my new battery too?

Good call getting a trickle charger - just got mine last week and it's good for my peace of mind.  I put it on for an hour or so once a week.

Don't take my advice, I don't really know for sure, but I doubt there's anything wrong with your charging system that would overload the battery.  I've only heard of alternators failing to deliver enough current, rather than delivering too much (or delivering an overvoltage) - and generally I'd always heard that motorcycle alternators were generally underpowered, hence the need for a trickle charger.  I'd wait for someone more authoritative to confirm this though.

Being a grad student in electrical/computer engineering I should really know a bit more about electrical systems, but anything over 3.3 volts is out of my league.  Looking forward to hearing more about the details...

[codynotes]

Thanks for the reply asobi. Yeah, the trickle charger will be a good call in any event, since I live in the city and weekdays I only drive short distances. I didn't think the charging system would be able to screw up the battery, either, so the fact that you agree gives me more peace of mind. Oh, and coincidentally I happen to be a graduate student in computer science/electrical engineering, too, but I don't know anything more than you, so don't feel bad

[sledge]

From what you say I dont think there is a problem with your bikes charging system. I think you drained the original battery so low you killed it dead and it wont accept anymore charge as a result, if the new one is holding up there shouldnt be a problem so long as you dont let it drain again.

There are 3 components to the bikes electrical system, the alternator, this puts out out 3 phase AC at about 75v at about 5k rpm, the rectifier, which converts the 3 ph AC output to DC, and the regulator, which governs the amount of voltage/current in the bikes system dependent on engine speed, current demand and the state of battery charge (determined by its internal resistance....I think( what say you starwalt?)).

Some things to consider.......
Any overcharging problem is generally down to a faulty regulator/rectifier. Expect lots of blown bulbs or to see a brighter than normal headlamp or one that increases in brightness with engine revs if its duff. Your battery will get hot, spew out acid and die a very quick death if its being overcharged. Anything above about 15v across the battery at 5k indicates overcharge.
Undercharging is indicated by a  voltage of less than about 13.5v across the battery with the engine running at about 5k and the headlight on high-beam. It could be a duff R/R or alternator or battery or any combo` of the above 3 at fault.
Running at less then 5k does not generate enough power to significantly charge the battery. Even at speeds above 5k it needs plenty of time to charge.
Off-load battery voltage means nothing, what matters is its ability to deliver current when under load. To test this you need a DC ammeter and a resistive load-bank.

[codynotes]

Thanks for the info sledge. My headlamp is not any brighter or dimmer than normal, and its intensity does not change when the engine revs. I guess then that my previous battery hadn't died from overcharging, because there was definitely no spewing of acid =) I measured the voltage of the new battery with the engine revving to 5k, and it reads 13.6 V, so everything seems good there.

[starwalt]

...and the regulator, which governs the amount of voltage/current in the bikes system dependent on engine speed, current demand and the state of battery charge (determined by its internal resistance....I think( what say you starwalt?)).

Man, what are they teaching in undergrad and grad school these days?? 

Well said sledge! The battery chemistry is what changes as it depletes or increases in ampacity. The normal check of a battery chemistry is the specific gravity of the solution inside (the acid). All of the service manuals show the use of a hydrometer to do this.

You say the acid is fine but it still won't hold a charge? The plates are either coated in lead sulfate or disconnected somehow. Regardless a new battery is in order.

Lead acid battery technology is way over 100 years old. The electronic technology is what keep changing and growing.  BTW there will never be a 3.3V GS500. 

[asobi]

...and the regulator, which governs the amount of voltage/current in the bikes system dependent on engine speed, current demand and the state of battery charge (determined by its internal resistance....I think( what say you starwalt?)).

Man, what are they teaching in undergrad and grad school these days?? 

Well said sledge! The battery chemistry is what changes as it depletes or increases in ampacity. The normal check of a battery chemistry is the specific gravity of the solution inside (the acid). All of the service manuals show the use of a hydrometer to do this.

You say the acid is fine but it still won't hold a charge? The plates are either coated in lead sulfate or disconnected somehow. Regardless a new battery is in order.

Lead acid battery technology is way over 100 years old. The electronic technology is what keep changing and growing.  BTW there will never be a 3.3V GS500. 

Meh, the battery on my GS is sealed.  I've read the Clymer manual sections on battery maintenance but I don't think there's an easy way for me to know when the battery's kicked the bucket other than obvious symptoms.

[sledge]

Sealed batteries can be tested. Take it to an auto-electricians shop or a tyre/battery outfit and ask the to load test it for you, if you are lucky they will do it for free.