Should motor/lights still run with battery disconnected?

Energy One

Ed U. Cator

Higher Ed.
Each of the last 3 Duracell AGM batteries work fine for a month or two then without warning, they go dead & won't take a charge. Dealership's battery analyzer showed each time batteries below 10v & amperage capacity too low to even light a LED headlight. V- reg. charging voltage is 13.4 to 14.4v but I noticed that disconnecting battery while motor in running causes it to stop & lights out. Is that normal or is the VR not outputting enough amperage but correct voltage? Incidentally the VR was replaced a few months ago.
 

mleach72

Well-Known Member
Each of the last 3 Duracell AGM batteries work fine for a month or two then without warning, they go dead & won't take a charge. Dealership's battery analyzer showed each time batteries below 10v & amperage capacity too low to even light a LED headlight. V- reg. charging voltage is 13.4 to 14.4v but I noticed that disconnecting battery while motor in running causes it to stop & lights out. Is that normal or is the VR not outputting enough amperage but correct voltage? Incidentally the VR was replaced a few months ago.
Yes, motorcycles aren't like a car. Bikes have a stator. Cars have alternators. Bikes run off the battery and the stator keeps the battery charged. That's why when you disconnect the battery, the motor dies. Once a car is started, the alternator runs everything.
 

mleach72

Well-Known Member
Each of the last 3 Duracell AGM batteries work fine for a month or two then without warning, they go dead & won't take a charge. Dealership's battery analyzer showed each time batteries below 10v & amperage capacity too low to even light a LED headlight. V- reg. charging voltage is 13.4 to 14.4v but I noticed that disconnecting battery while motor in running causes it to stop & lights out. Is that normal or is the VR not outputting enough amperage but correct voltage? Incidentally the VR was replaced a few months ago.
Are you keeping a tender on the battery? I had this problem. I have to disconnect the battery before I put the tender on. If I put the tender on with the battery hooked up, it kills the battery in about a month.
 

Sven

Well-Known Member
Is this voltage reading test run with a cold engine? As if the engine/crank/case/stator is cold on the test, rather than a long run to heat the stator. Therefore, don't turn the bike off, take what it takes to pull the seat, etc., then test the output running at idle/blip and all that.

I could be wrong, but I apply the theory; Magnetism: you cannot separate heat from its chemical reaction. So if I apply;
1. Heat = expands and shorts when hot.
2. ChemRe = Battery acid is not cooked/mixed well enough with a low voltage output of say 12v when hot at the meter. The need to up the heat to 14v is (wink-wink) the better number of heat so the acid to water does not 'separate'.

Theory make sense?
 

Ed U. Cator

Higher Ed.
Thanks for replies thus far. To answer some of your questions, my Battery Minder (for AGM SLA Odessey etc.) gets connected with battery wired in place. Seems unnecessary + a pain to have to isolate the battery before using the Minder each time. Batt Minder gets connected only when bike is gonna sit for more than a few days.
Silly me didnt stop to think further about the stator vs alternator diff. - thanks for the reminder! The VRs output was tested on both cold & warm engine w/ virtually same results. Been wondering if I happened upon a bad mfg. run on 3 Duracell Powersport batts? I doubt they are Deka clones. The Deka has better exterior construction that's visibly obvious. And yes I have a batt. charge monitor attached that displays temp, voltage, % remaining charge.
 

mleach72

Well-Known Member
Thanks for replies thus far. To answer some of your questions, my Battery Minder (for AGM SLA Odessey etc.) gets connected with battery wired in place. Seems unnecessary + a pain to have to isolate the battery before using the Minder each time. Batt Minder gets connected only when bike is gonna sit for more than a few days.
Silly me didnt stop to think further about the stator vs alternator diff. - thanks for the reminder! The VRs output was tested on both cold & warm engine w/ virtually same results. Been wondering if I happened upon a bad mfg. run on 3 Duracell Powersport batts? I doubt they are Deka clones. The Deka has better exterior construction that's visibly obvious. And yes I have a batt. charge monitor attached that displays temp, voltage, % remaining charge.
I'll bet it's the tender. It sounds like the exact same problem I was having. I went through 3 batteries before I figured out what the problem was. It might only be certain years of big dogs, or certain types of tenders, but there is something that doesn't mix well with the tender and the electrical system.
 

Th3InfamousI

Administrator
Staff member
To go through 3 is odd to all be in same batch but I'd there any manufacturing date? Could be old stock?

Sent from my 2PS64 using Tapatalk
 

Ed U. Cator

Higher Ed.
Th3Infamous!:
No old mfg dates- all 3 batteries coded from earlier this year (Jan-March). Did voltage checks of the new Deka from yesterday morning to this morning. Regardless of motor running from cold/warm/at rest, battery voltage was no more than .3v difference. Seems acceptable to me. Next weekend's bike event will give me the opportunity to do more testing & monitoring.

mleach72:
I'm using a Battery Minder # 128CEC1 not a Battery Tender which is similar but different in features & operation. Instructions don't mention any importance of removing the battery before using the Minder. I have wondered though how these smart chargers/maintainers compensate (if possible) for live circuits like the EHC that's connected across the battery at all times.
 

mleach72

Well-Known Member
Th3Infamous!:
No old mfg dates- all 3 batteries coded from earlier this year (Jan-March). Did voltage checks of the new Deka from yesterday morning to this morning. Regardless of motor running from cold/warm/at rest, battery voltage was no more than .3v difference. Seems acceptable to me. Next weekend's bike event will give me the opportunity to do more testing & monitoring.

mleach72:
I'm using a Battery Minder # 128CEC1 not a Battery Tender which is similar but different in features & operation. Instructions don't mention any importance of removing the battery before using the Minder. I have wondered though how these smart chargers/maintainers compensate (if possible) for live circuits like the EHC that's connected across the battery at all times.
I think it's just with these bikes. I have the harley supersmart, which is probably similar to what you have. It works just fine on my Harley with the battery connected. If I put it on my big dog with the battery connected, the battery is dead within a month. Charger says the battery is fully charged, but not enough juice to start it.
 

mleach72

Well-Known Member
You don't have to remove the battery, just disconnect the leads. What you described is exactly what I went thru 7 years ago. Once I figured out that it was the charger that was doing it, I haven't bought a battery since. 7 years old and still going strong.
 

Ed U. Cator

Higher Ed.
I think it's just with these bikes. I have the harley supersmart, which is probably similar to what you have. It works just fine on my Harley with the battery connected. If I put it on my big dog with the battery connected, the battery is dead within a month. Charger says the battery is fully charged, but not enough juice to start it.
That's just crazy but I don't doubt you since I'm experiencing practically the same. Batteries showed good on analyzer & charger. Start up bike w/ no problems, go out for a ride, stop for awhile to enjoy a meal, start up bike to leave & I'm stranded! This last time I was lucky it conveniently happened at a bike dealership!
 

Sven

Well-Known Member
Remember, this is just a variable as with the charger scenario. But I shit you not, I just now walked in from the garage... being schooled by 'Reach Around Universityou Idot.' See, I get this call from the nephew, says the bike won't charge. I walk him thru the meter steps, tell him to pull the battery and have it checked. Batt checks good.

Same thing happens again. I now go over and check myself. Posts are tight. Stator shows no ground to itself. VR shows it can adjust the volts. WATT GIVES? I start the bike and the idle reads 14+. I'm not going to reach around for my wallet and start throwing parts at it. Ride it.

Days later I get a call, said to ride it around so the bike (stator) is hot enough to see where the volts are now at idle? He says 12+. So I apply my E-theory, call the ball and say it's hot when it fails, buy a stator. He calls from the dealer, says the counter guy says to buy a VR as well because these evos are notorious for failed stators and VR?

Shrugged my shoulders and said to get both. Noticed the original had thinner gauge copper windings. The updated(?) shows thicker windings. The stator was installed. Now to lace the VR wire and copy the factory routing and zip tie points. As I remove the wire completely out, I noticed it was rubbed thru. No way could you have caught that between the back of the oil tank to frame to main harness it sat under. Was it smoked as in a spark or current draw occurring? No. Because that wire goes to the 30a main silver side stud and would have killed everything. So it just rubbed thru on something. Or say, not enough to rub off the paint to touch ground? No.

I think this is where I should add how 20/20 Hindsight now kicks in; or how I paid for that tuition. What I did discover however, was the wire connector end of the (+) side of wire to the battery; finally fell off the end of the wire. Bad crimp job. Yeah, and also found a horseshoe type half of a connector behind the 30a silver stud too. Looked as if the previous owner(s) tore off their accessory connector end. As the battery was in the way of snipping a few zips, I found the eyelet connector end on the bike lift. That was its last straw.

This says I'm going to go with a heat variable at the (+) connector end off the battery side. So I'd tug on the wire and see if the connector can hold that wire in.

Signed,
Who The Fuck University Knew (graduate).
 
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