I actually work with automotive ECU firmware and that's our biggest issue which is battery voltage fluctuations or transients so I'm somewhat familiar with batteries and DC systems in general. We do quite a bit of under/over voltage testing and how our firmware behaves.
I called my local BatteriesPlus and asked about the possibility of them providing an AGM battery to fit my 12N/YB12 specs. In short NO.
Their reponse ...due to the AGM batteries being sealed at the factory and that the factory builds them to their own specs AND that there isn't a large demand for the battery size, they couldn't provide or build an AGM battery in the 12N/YB12 size they also added that unfortunately "The battery shrinker is on the Fritz"
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!!
So it looks as if the battery from the online place is still the solution.
I'm wondering if we could possibly find the same item elsewhere though.
As far as the configuration of the battery cables...
At least on my bike, perhaps it's been modified by the PO, both of my battery cables have been trimmed to line up with the battery posts with little if any excess.
My (-) cable is only about 6-8" long and bolts to the rear of the tranny case so it wouldn't be able to stretch to the other side of the battery even if I wanted to. Thus a battery configured opposite to that specified wouldn't work at least on the grounds of the existing ground cable wouldn't reach.
Of course you could extend them etc. but since I'm planning on a new battery anyway .... its a moot point now.
I do have a battery tender and after having acquired the bike and going thru it I'd topped off the battery with distilled water it still loses charge .5V/2hrs w/o the ignition even turned on.
That's why it's NEW Battery Time !
I love the bike though and can't wait to see how she runs with a fully charged battery !
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Regards