Maybe the op would be kind enough post a picture of his battery compartment as it is right now, like the one MOB posted. Along with a pic of his battery.
that would go a long way to help, for sure, especially identifying/showing the actual wires, and points where "the smoke came out/was released"....(sorry, just a little electrical joke about "the magic smoke") but pictures would help greatly....
Can a defective battery with an internal short create the same symptoms? If the battery were hooked up backwards, what can he expect when it's hooked up properly?
well, short answer, no, the occurrence with an internally shorted battery would not result in that; when a battery shorts "inside" it basically removes the capacity for "full voltage" at the point of the short; There are 6 sets of plates,each supplying approximately 2 volts (=/- a % of that), if a short occurs between the first and second set, the output volts will be like 9-10v, or 2-3v, depending on which end of the stack it occurs to. If a battery is installed in THIS bike, as long as the ignition is off, minimal sparking will occur at any terminal... and when attempting to start the bike after, it will not start. Removing the battery, and replacing it correctly, works fine; or so we have seen by the numerous reports on THIS BIKE when they have been incorrectly installed (was very common a few years back, to see this occur even from the dealers...
), and so far, after reversing the battery, and connecting it right, no further problems of "catastrophic" damage was found. I guess it's a testament to the robust nature, and safety built into THIS bikes design... or, just plain luck.
Now, if a battery with an internal short, is JUMP STARTED, of forced to take an outside current flow, which it now cannot do because of the short... it COULD blow sky high, and at the least, it will melt down the jumper cable in short order, as its basically like connecting the cable ends, from a running engine sending charging current...
I've had to run outside and put someones "burning" car out with an extinguisher at work, when they attempted jumping a shorted battery... it was pretty impressive to see how fast things "went south"...