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Discussion Starter #1 (Edited)
I just bought a 2005 r6.
I had the bike running for a few minutes and turned it off. Went to restart it a minute later and it wouldn't start.
I did accidentally leave the high beam on while the engine was off. Although the lights don't go on while the bike is off, I'm not sure if that could have been the problem.
It was attempting to turn over but just didn't have enough juice. Tried a few more times but the battery was only getting worse.
I followed the troubleshooting procedure in the service manual. I tested the stator and seemed to be fine.
I decided to jump the battery and the bike started.
While running idle the battery was charging back up to around 12.3-12.5V.
Sitting idle with the high beams on, the battery dipped to around 11.6V.
with high beam off and giving some throttle at roughly 4k rpm, it was sitting around 13.5-13.6V.
Ran the bike for 10mins. After turning the engine off and key at off position, the battery slowly decreases to 11.8V

unless I'm mistaken, it seems the stator and rectifier are ok given the 13.5-13.6v range with the throttle.

Any suggestions? Could it have been from the high beam switch being left on?
Is 11.6V at idle with high beams normal?
btw, the previous owner mentioned he replaced the battery, not sure how long ago or if it was from the previous season.
The battery at least looks new and I assume he meant he recently replaced it but I cant say for sure.
battery is a Powerstar PM9-BS
Thanks.
 

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Charging systems in general are not designed to charge a dead/dying battery. Attempting to do so can damage the charging system. I had a car battery that failed in kind of a weird way where it had plenty of cranking amps, but no capacity. I only discovered the issue after sitting in the car, listening to the radio for less than an hour. Running the hazard lights for five minutes would kill it. But charge it up and it would briskly crank the engine no problem. Also, many batteries fail to recover after being completely drained.
 

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YZFR6... ooodles of HP
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Yep, sounds like a completely dead or ruined battery. Trickle charge for a couple days and if it still has problems, it is kaput.
 

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BTW, if you do NOT ride in cool weather...
...they store well. Price is negotiable; just throw up an offer.
 

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Discussion Starter #5
Thanks for the info.
Every time I ride, the resting voltage with the engine off is getting better. Now when I cut the engine off, it lowers from around 12.6v and settles at 12.2V.
I might just keep an eye on it and see how it goes. I'm also thinking of replacing it just to stay on the safe side. If a low-capacity battery can put my charging system at risk, I might be better off just replacing it.
 

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I think there was a misunderstanding. The reason why it's not good to use your vehicle to charge a dead battery is due to the heat that the system generates when running near or at full-field. It wasn't designed to do that for "extended" periods. The low capacity battery I had was okay to run on because it had a short recharge time; the vehicle could charge it back to proper voltage (capacity) in little time. After parking over a steamy sewer for a week I popped the hood and it was literally raining under there. Everything under the hood aged like ten years. Unbeknownst to me it had compromised grounding between engine and frame/battery. The weak grounding caused the charging system to misread battery. So it kept charging full-tilt the entire time. I hadn't figured that out until it killed the third alternator inside six months...
 

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YZFR6... ooodles of HP
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Not to mention low charge state batteries don't like the high rate of charge that the voltage regulator commands.. hence boiling of the electrolyte. Trickle charge the ******!
 

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The connector to the rectifier/regulator has 3 AC terminals going in, and 2 DC terminals coming out. Check the Vac going in across all three phases when running, and check the Vdc coming out (feeding back to the battery).
I can't remember the numbers off the top of my head, but the Vdc should be around 14 V, and drops to 13.5 ballpark when you turn the high beams on.
 

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Not to mention low charge state batteries don't like the high rate of charge that the voltage regulator commands.. hence boiling of the electrolyte. Trickle charge the **!
Would a faster charge rate prevent or reduce calcifcation with a standard (not AGM or Gel) lead-acid?
 

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YZFR6... ooodles of HP
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Not sure, but constant low charge voltage increases calcification of the plates. Maintenance mode I think bursts amps then drops and bursts and drops to de calcify a gel ie optima type.

I meant if it's got low volts, the best care is to trickle charge it back to full charge. Then resume alternator control. Vs letting the alternator peak charge a dead or low battery. On the side of the road a jump is the only option but at your house you can wait a day to do it right.
 
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