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Discussion Starter #1
Please help me again folks. My battery doesn't appear to be charging while I am riding the bike. I had the battery checked and was told that the battery was good, just needed charging. I put the battery on a maintainer every night. After being jumped off this morning, I rode 16 miles and the battery wouldn't turn the engine over. I ride a 2005 with 22K. Any suggestions?
 

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Pop the seat off, get a digital voltmeter and post the battery terminal voltages with engine off, at idle, 2k, 3k, and 4K rpms.

Jon
 

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Just to elaborate on Jon's point: our batteries get recharged by a stator and regulator system that kicks into action only above a certain level of rpms (2500 or so). Below that, the motorcycle is largely operating off the battery and will do so until the battery conks out.

So you'll want to grab a voltmeter and test the voltage at idle (should be about 12.7 v), and then increase the rpms to 2000, 3000, 4000. By the time you hit 4000, your voltmeter should be reading 14.5 v or so (now your motorcycle is running off the battery and the voltage being produced by your charging system, but there's ample voltage to replace what's being lost by the battery).

If you're tendering the battery overnight and it's not getting up to working voltage (i.e., 12.7v), I'd suspect the battery itself. If you can get it charged, get it to start the bike, but it loses the charge in short order, suspect the charging system. It's a common problem with these bikes, so holler if you need any help with this.

Good luck!
 

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Giggity!
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Just to elaborate on Jon's point: our batteries get recharged by a stator and regulator system that kicks into action only above a certain level of rpms (2500 or so). Below that, the motorcycle is largely operating off the battery and will do so until the battery conks out.

So you'll want to grab a voltmeter and test the voltage at idle (should be about 12.7 v), and then increase the rpms to 2000, 3000, 4000. By the time you hit 4000, your voltmeter should be reading 14.5 v or so (now your motorcycle is running off the battery and the voltage being produced by your charging system, but there's ample voltage to replace what's being lost by the battery).

If you're tendering the battery overnight and it's not getting up to working voltage (i.e., 12.7v), I'd suspect the battery itself. If you can get it charged, get it to start the bike, but it loses the charge in short order, suspect the charging system. It's a common problem with these bikes, so holler if you need any help with this.

Good luck!
You know... Pretty soon you'll be teaching everyone else here! lol (but serious)
 

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I agree with Kanuk69 and Corbins365. I've been chasing down a host of electrical issues and a non-charging battery was the last (cross my fingers). I followed the steps above and it lead me to checking the charging system. My rectifier/regulator needed to be replaced. Good luck.

-Tim
 

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You know... Pretty soon you'll be teaching everyone else here! lol (but serious)
Ha ha - that's what happens when anthropologists can't get academic jobs. We learn a whole new trade in the hopes of finding another outlet.

Seriously, though, I'm a better fixer when I understand how things are s'posed to operate, but if folks find that annoying ("just tell me what the meter should read, darn it!"), feel free to tell me to knock it off. :D
 

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Discussion Starter #8
Update on my charging problem

I left the maintainer on all day and the light was green indicating that the battery was charged. When I tried to crank the bike, it would not even turn over. The starter just clicked. To me, that sounds like a bad connection or a bad battery. I have not had a chance to check it with a volt/ohm meter. Again, thanks for everyone's help.
 

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It could be the starter or wiring thereto (the click was your relay - so that's good!); it could also be that the battery has just enough oomph to give the charger the green light, but not enough to turn over the engine. When you get the chance, check your voltage (I've found with McKnight that 12.3 is too low). If that's ok, then check all of your ground connections (negative battery terminal to ground; back of the engine case to the battery box; starter motor to the relay. All grounds are thick black wires) - look to make sure they're really contacting metal (not dirt or paint), and that the connections are good and tight.

Did you say you got a jump start for the bike the other day? And then the battery was dead by the time you got to work? If you can jump it now, that'll be a quick diagnosis. If you DIDN'T jump it before, here's what you do:
make sure the car is not on, running, or anything - you're just borrowing the battery for a moment. Pos to car battery pos; pos to bike battery pos; Neg to car battery neg; neg to bike ground. If it starts, then seems like the battery is the culprit.
 

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I'm still not sure if it's an old maintenance battery or a "sealed" maintenance free battery!?
A regular wet cell will have some form of removable caps, either individual screw in type or a plastic pull tab with nubs that go in the cell holes. If it'[s one of these, you really need to inspect it once a week for fluid level. You'd be surprised how much electrolyte comes out of the vent hose in a week. Low electrolyte is bad for our charging systems as it changes the internal resistance of the battery and causes stators and R/Rs to fry.
A M/F battery will be completely sealed with some form of tape that won't come off easily. It also will NOT have a drain hose or other large vent that allows fluid to come out. Because of this, there is no fluid to check, no acid to spill on various parts of the bike, and no weekly fluid level check!! Internal resistance stays stable so the charging system is happier.
 

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Benjammin'
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Just to throw this out there-
A battery can measure 12+ volts and still be bad. You said you had it checked and it was 'supposedly' good. The real test of a battery is under a load such as what a starter needs. Take the battery to a shop or parts store that has a load tester. I believe some folks have taken their batteries to Autozone for proper testing.

Also- you mentioned the bike was jumped off another bike? If so, then that would lead me to believe the starter is working fine, if another bike's battery works to start it.

In any case, a MF battery is a must for our bikes. Not necessarily an expense we like to lay down, but I am convinced several other runnability issues were cleared up when I got mine.

Good luck and keep us posted!
 

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Giggity!
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I've actually heard of (through another source) the stator going bad and charging the battery ( externally at home to start the bike ) and still riding. Now I've never experienced this & don't want to but it makes me think of older bikes & how they ran!?

& C, It's a bunch of over active gremlins kept busy! lol
 

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Because the stator dumps power all the time I think you are better off with a slightly weaker battery and maybe a few accessories. This way the excess power has a place to burn off reducing heat in the R/R and stator. I think a top quality MF battery just adds to the problem.
 

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Nope, becaue the internal resistance of the weaker battery just loads the R/R down more generating more heat which fries the R/R which usually fries the stator. ;)
Too many folks here have recommended the M/F battery and thier experience belies what theory may suggest. Besides, the M/F batteries are really only about 20-30 bucks more than a conventinal wet cell anyway. With stators at 100-140 and R/Rs at 100. it's cheap insurance.
I'm convinced a wet cell battery that was low on electrolyte is what caused my R/R, stator to go. I didn't know about the weekly inspection then or the problems a conventional battery could cause.
For the record, even though my stator and R/R are well out of spec for resistance measurements, my battery is still being charged. I'm waiting for the charging system to fail completely before I change them out just to see how long I can get away with it. Fortunatley, my commute is now only about 4 miles or so, so walking home isn't a problem. When I do replace them, a M/F battery will also be on the parts list.
 

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Discussion Starter #17
Second update on my charging problem

I determined that the battery was bad so I bought a maintenance free as everyone suggests. I charged the new battery. It cranked the bike without any problem. The output was about 12.5 at idle up to only about 13.5 or 13.6 at 4000 Rpm. Will that do or do I have some other problem?
 

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That's a little low at the higher rpm (should be about a full volt higher)... you might want to check your stator wires (all three wires are yellow - check the resistance between any two leads, and it should be between .3 and .5 ohms). If the leads test ok, I'd suspect the regulator - but that's a CHEAP and EASY repair by comparison, so it's well worth the investment (anything that doesn't require an engine pull is worth the money!).

Jim, I completely second you on the wet cell batteries and our charging system issues. Maybe if the r/r were relocated, the cooking wouldn't occur so quickly with the higher output required on the dying battery, but I know that's what blew my r/r in my '92. Wet cell, hot day, blah, blah, blah. Besides, I'll gladly pay $20-30 to keep battery acid from making creative etchings on my frame.
 

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Cindy,
That looks like an old DOS game where you moved bridges and dropped bombs to get the little critters through a maze. I probably still have the 3 1/2" floppy with the game on it. Never did make it to the last level.
 

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Old Truck Junkie
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Because the stator dumps power all the time I think you are better off with a slightly weaker battery and maybe a few accessories. This way the excess power has a place to burn off reducing heat in the R/R and stator. I think a top quality MF battery just adds to the problem.
The stator only generates what the regulator tells it to generate. The more accessories the more the regulator requires from the stator. And the better the battery the less energy that has to come from the stator.
 
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