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Bat. in parallel

Electrical issues
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chuck58pan
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Joined: Sat Oct 01, 2005 3:18 am

Bat. in parallel

#1

Post by chuck58pan » Fri Jan 16, 2009 11:38 pm

With all the battery info it seems difficult to come up with a strong set-up. my horseshoe is still marinating hope fully it will return to service. for now i am intending on running 55 police . ther is plenty of room for a batt. my thought was is it a poor idea to tie two 7ah. batts. in parralel. im intending on putting an led 1156 or 1157 for a tail with turn signal and spots up front the headlight had a spliced-in 3prong plug dont know what bulb other than 6v. sylvania I took the middle contact out of the lamp-conector hoping to run wire directly to it but the wire- crimp is tight, i may find someone with those contacts. anyway the original batt. was 18ah, would going under the factory spec and running spots create a problem. the batts. are conventional lead-acid type. they appear to be high quality and that is my primary concern. thanks Chuck



john HD
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Re: Bat. in parallel

#2

Post by john HD » Sat Jan 17, 2009 12:41 am

chuck

i deleted your duplicate post.

yes you can run batteries in parallel. here are the issues, they need to be the same size, same age, same general condition. otherwise they will "fight" each other, meaning the weakest one will always be drawing current from the stronger one. however, if one fails you can simply disconnect it and carry on with half the capacity.

the other option is to take 2 6v batteries and run them in series, this will give you the voltage i assume you are running by your selection of tail lamps. the advantage is that the batteries will work together and provide more amp hours of current than 2 of the same size in parallel. the disadvantage is that if one fails you are done, load it in a truck and take it home.

if you really want to make your head spin, google "peukert's law" and see how it pertains to battery life.

you may be better off to find as close as possible a battery of the right size to fit your police tank (of the correct voltage) and run just one.

john

FlatHeadSix
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Re: Bat. in parallel

#3

Post by FlatHeadSix » Sat Jan 17, 2009 2:10 am

Thanks a lot John!, you deleted the other post just as I was submitting my response and it got dumped. My answer was pretty close to yours so its OK.

I think Chuck is still running 6 volts so he does want them hooked in parallel, pos to pos, neg to neg. I ran a pair of Superior (Dixie) cheapies hooked up in parallel, taped together, and dropped in the battery box on top of a chunk of 2x4. They lasted several seasons and would probably still take a charge if I took my time, no problems with the generator or lights, worked just as good as an OEM H2.

Chuck, the amp rating on the battery only determines how fast it will take a charge without overheating and how long it will keep the lights on when the engine is not running and charging it. A smaller capacity battery (or pair of them) should be charged at a slower rate. It won't matter how many lights you run as long as the generator will match the load without working itself to death, the battery really has nothing to do with it, its all about the capacity of the generator. Kick start bikes don't need a lot of cold cranking amps so your pair of 7 amp units will do just fine.

mike
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chuck58pan
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Re: Bat. in parallel

#4

Post by chuck58pan » Sat Jan 17, 2009 5:00 am

Thanks John,I am not too savvy w.the comp. thanks again to both of you for your replies. I want to be as solid as possible in the electrical end. I have the 12v set-up but I went to some time and expense to put my 6v. coil, generator and reg. back into service.(Dale Cashman)His work along with Perry Reuter,Don Sullivan,Cotten have made the possibility of getting it back together a real possibility.the # on the tail bulb may be off its the 55-64 or up deal i may just hang with the original for now due to the need to put some light up onto the licence tag (not to difficult i suppose but i have my hands full getting it rolling. caught myself putting brake fluid in my fork tube ;never would havethought about till i went to fill the other side. thanks, Chuck

chuck58pan
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Re: Bat. in parallel

#5

Post by chuck58pan » Sat Jan 17, 2009 6:02 am

thanks Flathead six for the pix got my but off this chair and out into my freezing cold eastern pa. garage to measure the batt tray.(baby steps) i would be sitting on the fence wondering what the perfect deal would be . this way the measure for the two is cllose to a fit so i went for it ( "a faint heart never screwed the mess-cook"). I appreciate the effort, c
huck

john HD
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Re: Bat. in parallel

#6

Post by john HD » Sat Jan 17, 2009 6:12 am

Thanks a lot John!,
just doing my part mike!

hey that petcock on your bench looks like every other one i had like it, either leaking or on the bench in parts!

where is the beverage to go with the ashtray?

john

steve_wood
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Re: Bat. in parallel

#7

Post by steve_wood » Sat Jan 17, 2009 12:35 pm

I bought two (2) of those petcocks (they are for old sportsters) from V-Twin (via J&P) and BOTH of them leaked. Thankfully, J&P refunded my money.

FlatHeadSix
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Re: Bat. in parallel

#8

Post by FlatHeadSix » Sat Jan 17, 2009 3:42 pm

Don't get me started on those petcocks, I put them in the same category as the repop fuel tanks that VT hates so much. All the vendors are selling the same junk from the same supplier, I'm guessing that Tedd commissioned them and everyone is reselling from the same batch. They either leak or they won't pass gas at all (in this case passing gas is a desirable thing).

Steve, Harley used them on the old sporsters and several other applications but they also put one of those on every Hummer that came out of Milwaukee. I would think that there is a big enough market to justify making replicas that worked as good as the originals and I'm sure that the folks that need one (just about everybody with one of those bikes) would be willing to pay a few extra dollars for one that worked.

Maybe we could get VT to add those to his campaign for better repop products.

John, I think I set the beverage on one of the stools when I took that picture, I'll make sure to include one in future pics....

mike

FlatHeadSix
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Location: Lonoke, Arkansas

Re: Bat. in parallel

#9

Post by FlatHeadSix » Sat Jan 17, 2009 3:55 pm

oops, I forgot to add the link to Superior Cycle Products (Dixie). I don't think you can beat these guys on price for their batteries and they seem to be good products. The specification chart also shows all the dimensions as well as the configuration of the posts and vents etc., very helpful. Another plus is that they ship them with the acid pack, most suppliers won't ship the acid. And, for some reason that I still can't figure out, they're kits which include the acid pack are CHEAPER than if you just bought the dry battery?????, go figure. give 'em a try.

mike

http://www.superior-cycle.com/

john HD
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Re: Bat. in parallel

#10

Post by john HD » Sat Jan 17, 2009 4:37 pm

mike

when i was running 60's era 5 gal tanks i had about 4 of those petcocks in various states of disrepair. and as you pointed out they either would do nothing or leak.

i finally got fed up and bought an accel petcock. no more leaks. that was one of the few accel items i ever bought that lasted more than a year.

chuck,

don't be afraid to go to your local batteries plus or battery mart and ask what they have. (you may want to take your oil tank with you) you may be pleasantly suprized at what they have. some even stock the H-2 for very reasonable prices. every time i have gone to one of those places i have come out with something usable, my last dilemma was finding a set of batteries for a vintage motor generator welder i own. they had the correct ones in stock!

john

steve_wood
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Location: Belleville, Ontario, Canada

Re: Bat. in parallel

#11

Post by steve_wood » Sat Jan 17, 2009 4:42 pm

Mike and John:

Those darn petcocks. I have two originals for my sportster, but one developed a seep after being on the bike for a while. I suspect that there might be rubber inside that cannot stand up to the P4Gas we get today. The other original is perfect, but it's safely stashed away. I also gave up on those repop petcocks and I'm gonna install an accel this spring. The two originals will go with the bike if I ever sell it.

Sorry for hijacking the thread. I'll shut up now.

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