Blew up another one....

[john jupiter]

Hi guys,

Looks like i have blown up another battery (this time a safa 6v).. The previous two were sealed MK batteries and i have used the standard b38 but had huge acid fizzing problems... I am thinking im over charging these batteries..

Does anyone know what the maximum voltage i should see at the battery after the rectifier/regulator?
I reved the engine to about 4k rpm and got 7.8 and was still climbing..

Thanks
John

[Jordan]

Have you read the widecase workshop manual supplement? It says the regulator is set to approximately 7.5V, so if working properly the battery shouldn't see much more than that at any revs.

Jordan

[DewCatTea-Bob]

By: john jupiter...
" i have used the standard b38 but had huge acid fizzing problems...
I am thinking im over charging these batteries.. "

____ Since you've started another new thread on this, (then for the sake of most readers), you ought to have confirmed which model your Duke is and if it's charging-system is completely stock or whatever !
I assume you're in reference to a stock Jupiter/(w-c.450) ? _ If not, then please include any related relative details.
__ When you get your (whatever particular) battery issues, such as the "fizzing",, I assume that it happens only when riding extensively with the headlight turned-off, correct ? _ In any case, please mention what the wattage-rating of your particular headlight-bulb is.
Also, I can understand how a 'sealed' battery could actually 'blow-up', but what's REALLY going wrong with your batteries - (the B38 for example) ? _ Did they get hot & warp their plates, or just reach a point when they no longer take or hold a charge,, or what exactly ?


Hopeful-Cheers,
DCT-Bob

[JimF]

Keep in mind the regulator is supposed to regulate. That is to say thee is a fixed voltage (charging voltage) that it should not rise above.

It would seem that your regulator is not regulating.

[john jupiter]

Bob, Jordan, Jim, thanks for the replies.
Same bike, decided to try a new r/r i found on ebay from a seller in italy.

Problem has been that the batteries would work fine one minute and then then go dead the next.. Well not dead, but not able to light the headlight or create a spark. They also wont take a charge. When tested after the problem has occured they always had around 6v but no amps...
Ive never tried the b38 for more than 20 miles or so.. It fizzes and splashes all over and has destroyed the paint on my chain guard and rear fender

Yesterday i charged up another safa 6v and my findings where the following:
reads 6.2v when nothing is on.
When bike is reved to 5k rpm with he headlight off the voltage measured by putting the probes on the battery terminals is 7.8- 8v
When headlight is turned on the voltage on the battery drops to about 6.8-7v at 5k rpm
I tried going out for a ride with the headlight on and still wound up with acid all over the place. also noticed that the horn wouldnt work with the headlight on unless i was above 4k rpm which is strange to me because i would think it would honk great from being overcharged

So i brought it home and put a Shorai 6v on it rated at 18amp hrs. (not sure what the amp hrs are on the other batteries at the moment).

Shorai results:
Reads 6.75v when nothing is turned on
When bike is reved to 5 k with the headlight on or off i get about 6.8v when taking reading from the terminals of the battery
Horn works while headlight is on at any rpm.

Im thinking the other batteries used previously might not have been strong enough to turn on the scr in my r/r...or at least my wishful thinking..

[DewCatTea-Bob]

" decided to try a new r/r i found on ebay from a seller in italy. "

____ I assume you mean a stock/Ducati-type r/r.unit ?



" Problem has been that the batteries would work fine one minute and then then go dead the next.. "

____ I assume you mean while riding ?



" Well not dead, but not able to light the headlight or create a spark. "

____ Well that's what most-others would call a battery whenever that's the case. _ However a battery that's REALLY 'dead' can't ever be used again, as it has then become permanently completely useless !



" They also wont take a charge. "

____ I assume that you mean when attempted charging is done with a suitable source other than by your Duke ?



" When tested after the problem has occured they always had around 6v but no amps... "

____ Well of-course that circumstance can also be normally common for a usable but well-discharged battery which could otherwise still possibly work properly IF it became stored with sufficient charge and still had the expected means to internally conduct it's stored power-juice. ...
However in this case of yours, I'm led to highly-suspect that if those (non-B38) batteries were to be dissected, it could then be found that one of their internal connectors between the plate-sets of the cells has been cracked-apart,, thus-then leaving only the electrolyte itself to pass (a relatively small amount of) current-juice (to [fool] your volt-meter), and so therefore normal/SUFFICIENT amperage is no-longer available (to run the loads normally). _ And (without internal repair), that certainly makes them really-DEAD batteries !



" Ive never tried the b38 for more than 20 miles or so.. It fizzes and splashes all over "

____ Acid-splatter is an EXTRA common-issue for the 450s ! ... Is your battery not well rubber-mounted,
and are your Duke's motor-mount bolts all torqued fully tightened-down ?



" I tried going out for a ride with the headlight on and still wound up with acid all over the place. "

____ Especially with the 450s, (it's probably not much due to overcharging-fizzing), VIBRATION is the word !
Your test-run with the charging-system well loaded helps prove that it's not gas-fizzing which mainly causes the leakage of battery-electrolyte.
It seems that you really need to mount your battery (with breather-hole caps) with significantly improved vibration-dampening for it's mounting into the frame.



" also noticed that the horn wouldnt work with the headlight on unless i was above 4k rpm which is strange to me because i would think it would honk great from being overcharged "

____ I've posted at least once before that this horn WITH lights issue is apt to occur due to the stock single ignition-switch connection not being sufficient to conduct enough current to fully power both of those high-draw loads at the same time.
Addressing that issue (as I've suggested elsewhere), helps the battery, (if fully charged), to more adequately power both those loads.



" Reads 6.75v when nothing is turned on
When bike is reved to 5 k with the headlight on or off i get about 6.8v when taking reading from the terminals of the battery "

____ All that tends to indicate a charging-system that's running in good-order !



" Im thinking the other batteries used previously might not have been strong enough to turn on the scr in my r/r... "

____ Not likely at all the case (unless the battery was low on charge & you also had the lights on, thus lowering the turn-on voltage too low),, besides, if the battery failed to turn-on the (stock-type) r/r.unit, then no charging at all could occur.


____ Bottom-line, it seems to me that vibration is certainly most-likely the main cause of all your varied battery-troubles.
__ If your in-town riding (with lights on) is kept relatively brief, then I suggest trying-out a fairly-smaller battery (than the B38), that's held suspended (from the frame-work under the seat), by rubber-strapping.



Hopeful-Cheers,
DCT-Bob

[Jordan]

Your voltage readings don't seem too wrong. I'm wondering if the acid spillage might not be related to overcharging after all. Could it be that the battery isn't mounted right, and vibration is causing the problems? Do you have a rubber mat under the battery?

Jordan

[DewCatTea-Bob]

" Your voltage readings don't seem too wrong. "

____ Right, as such normal-charging of batteries does cause some gas-fizzing !
To compare with abnormal EXCESSIVE battery-fizzing, try connecting-up a 12-volt (& over 2-amp)- battery-charger for a few minutes and THEN see the level of gas-fizzing that's then more likely sufficient to cause such aforementioned (6v.battery) troubles.


Hopeful-Cheers,
-Bob

[john jupiter]

I did not have a rubber mat.. Pretty incredible to me that its gone through 4 batteries in 500 miles from excessive vibration but i have lots of foam under the new battery and hope it solved the problem.

It seemed strange to me that the 6v Safa battery would have lower voltage to start but would read much higher voltage than the Shorai when reved.. Seems like something electrical is now working differently.

[DewCatTea-Bob]

" I did not have a rubber mat.. "

____ Jiminy-crickets! ... I-myself have very little doubt that many regular-type batteries could still possibly survive for long when fastened-down directly-against the frame of a 450's battery-mount without any cushioning-insulation !
That revelation now makes me pretty-certain that your batteries were shook to death !



" Pretty incredible to me that its gone through 4 batteries in 500 miles from excessive vibration "

____ Seems to me that if you could strap-down your very-own head directly to your 450's hard-metal battery-tray/mount, (and still be able to take it for a ride somehow), THEN you'd no-longer find it to be so "incredible" !



" but i have lots of foam under the new battery and hope it solved the problem. "

____ 'Help', yes,, but 'solve', not-likely completely ! ... You really ought to continue seeking better ways to help isolate your chosen batteries from such excessive vibration.



" It seemed strange to me that the 6v Safa battery would have lower voltage to start but would read much higher voltage than the Shorai when reved.. Seems like something electrical is now working differently."

____ Well yes, the more amp-hours a battery is rated for, the more difficult it then is for the charging-system to raise it's measured-voltage ! - (As such batteries act as larger loads.)
__ It seems your latest battery is a superior one...
So could you post a picture of your chosen/Shorai battery mounted in your Duke ?



Hopeful-Cheers,
-Bob