NOTE: ALL VOLT/OHM READINGS ADJUSTED AFTER THE FACT. THIS WAS DONE AFTER RECALIBRATING SWING NEEDLE UNIT AND RECHECKING VOLTAGES WITH FLUKE/BECKMAN MULTIFUNCTION UNIT.

Yoda saw me working on my bikes this morning and he started in on me asking why I keep taking my batteries out of my lesser used bikes in the winter time. He said it was a test of my comprehension of the ways of the Force, so I had to try to answer him as best I could.
I tried to explain to him that when it gets cold I mostly ride the Savage as 1) it is the nimble get around town bike and it has the saddle bags and 2) I am not going on a long trip in the cold so I don't need the touring bike so much and 3) I don't plan to be going over 100 mph or go out dicing corners at high speed when the wind chill factor would take the finger and ear temperature down to way cold very negative numbers, so I won't be needing the squid bike.
Because I don't ride the other bikes very much when it is cold, it is just plain smarter to take the batteries out and store them indoors (giving them a bump charge every month or so until spring time). This way the batteries don't go bad on me and I don't have to fork over big bucks in the spring for new batteries.
Yoda wasn't impressed with my logic, he thought my thinking was very poor and I missed the point about batteries entirely.
"Ah, my young Paduwan -- so little you know to think you know so much. For your ignorance, your challenge to go to Radio Shack and Harbor Freight is. Flow with the Force you must. A way to ride your bikes all winter long and not hurt your batteries you will discover. $20 here is -- a solution installed on at least one bike before the sun sets you must or your light saber you lose for another 6 months ..."
Shoot, I hate that. Just got my light saber back not more'n a week ago from the last six months screw up. I think he just likes picking on me and taking my light saber away for no good reason.
So, I take the 20 spot and head on out to Harbor Freight. I figured they must have the charger there as Radio Shack doesn't carry bike or car stuff. This thinking worked out pretty good, the girl behind the checkout told me they had a $10.00 float charger on sale for $5.99 this week. Spec on the charger was ideal for a bike, less than an amp output and it has electronics to keep the voltage to exactly 13.5 volts and the current goes way down to near zero when the battery gets "full" so it won't overcharge and boil out the battery. Money was right, it was on sale -- must be what Master had in mind.
Next stop, Radio Shack -- but why was I sent there? I didn't have a clue, but it did occur to me to go to the one nearest to the swamp. Maybe I could scope out what Master had in mind if I could maybe ask and find out what he had been looking at lately??
The girl behind the counter clearly remembered the old floopy eared rascal that had patted her on the behind as he left just last week. He had been asking her for audio termination supplies that were in a low cabinet that made her bend way over to get out the various stuff he said he was looking for.
Looking at the girl, I knew what Master was really looking at and I asked her a question just to get some verification. Yep, he never did buy anything ... just fingered the packages, dropped a few on the floor for her to pick up, chuckled some and left. She pointed out the cabinet where the various ocular misdeeds had been done to her so I went over and pulled it open.
Stereo stuff, plug ends, connectors and stuff. There were some that had more greasy finger prints than others, so I got a few of each well fingered type and went back to the counter.
I took out the charger and put it out next to the connectors. Hmmm .. the only clue from my quest challenge that seemed to apply was "you must have the solution installed on at least one bike by the time the sun sets". Something has to be installed --- hey, could he be after some method to quickly connect and disconnect the float charger to the bike?
I mean you'd have to take the seat off any of my 3 bikes to use the alligator clips that come with the float charger. If you could use a stereo jack to do the connection, heck you could just unplug it and ride -- then replug back in when you returned. Quick and easy ....
Of the packages I took out of the drawer, only two were same-same on the connection ends -- male/female versions of a simple inexpensive solder on stereo connector. I knew they had to be the ones because they were the cheapest ones. Well, relatively cheap anyway (it's Radio Shack, remember? Ain't nothing cheap at Radio Shack).
Also I noted that this simple uncomplicated jack could make a ground connection to the chassis with the threads that mounted it AND that the protruding male positive on the mating jack that would be in your hand would never be able to make a shorting connection to the battery powered jack (a consideration to worry about if you have ever directly shorted out a battery and damaged a screw driver doing it).
As long as you hit the hole, you would be safe on all fronts. Failing to hit the hole would not make a big flash and smoke, just a tiny spark from the charger's output. Since the jack is simple and the hole is relatively large, even Master Yoda could hit it after an evening of sniffing his funny smelling herbs and drinking his swamp root potions.
The two packages had enough connectors to do all my bikes but between the two of them they cost a good bit more than the float charger did at Harbor Freight.

I paid the nice lady, told her she had really pretty brown eyes (just to prove I had actually looked up once at her eyes) then I hopped on my bike and beat it back to the garage. I took out my soldering iron and my drill bits and a 1/4" National Fine (28 threads per inch) tap and immediately hit a wall -- where is a piece of metal that is exposed the outside of the bike that will allow you to tap the female connector directly into sheet metal to get a negative ground connection and still allow you to run a wire in a protected fashion over to the positive battery terminal? This is easier to say than to do, believe me.
I figured I'd try on the oldest bike first in case I screwed something up. Plus there isn't near as much sheet metal available on my squid bike so it would be the more difficult task anyway. After considerable study, I found a piece of sheet metal that met the requirements and I drilled and tapped me a 1/4-28 hole, ran the wire through a rubber grommet that was used to run the wiring for the turn signals, ran it out through the new tapped hole and hit a snag. First, if I solder the thing on to the wire how am I going to turn it 20 times to thread it all the way in? Next, the bumper isn't flat -- gonna look ugly and have a potential to rust up the hole over time from rain water. Not good.
Looked in my junk and found me an "O" ring that matched the male thread on the connector (which fixed the rain water issue) and it also took up 10 turns on the thread. I soldered the connector in place after threading on a piece of heat shrink tubing and then the "O" ring. Solder job went well, I then put the "O" ring on the threads and then shrank the tubing over the solder joint to make everything nice and water proof and strong.

Now, I made a big loop of wire inside the fender then I counter-rotated the connector 12 times (winding the wire counterclockwise) and then screwed it into the sheet metal 10 turns clockwise plus one turn to compress the "O" ring. Then I pulled the wire back back up through the fender into the underseat area through the rubber grommet all nice and snug. Then I ran the wire over under around and about until it came up to the solder joint where the screw on terminal was factory soldered and crimped on to the big positive red lead (so I had me some existing solder to solder the little wire on to to make a good connection).
Easy peasy so far -- then I proceeded to check to make sure I had continuity where I wanted it and a ground to the metal chassis where I wanted it. Yeah, so far so good -- now some red gasket sealant over the inside of the fender where the heat shrink tubing and the raw threads came through and are exposed to tire thrown water (can't have that nice metal to metal ground contact in those threads getting corroded).

You can see the little brown wire running here and there and everywhere going back to the rear fender. Time for the final continuity and ground checks and ......
Schist on a stick !!! It is leaking nearly 100 milliamps of current !!!!
I said me some things that would have cost me my saber for a year, easy. But Yoda wasn't around to hear them. Besides, cussing isn't totally darkside -- Yoda does it sometimes when I slide him off my shoulders down on his head by accident when we are doing his stupid old Force coordination training drills. He don't hold on all that good while he's all doubled over laughing at me ....
Check it again -- hey! no milliamps leak!! Check it again -- now it leaks. Switch the leads -- no leak, switch the leads -- it leaks. Touch the center post of the installed mating jack with the black point -- it leaks. Touch the center with the red point, it doesn't leak. WTF ??!!
Ah! Diode bridge in the regulator/rectifier -- shows milliamps leakage when current flows with the bridge, shuts off all current flow when current flow tries to go the other way -- that's how it turns AC from the stator into DC. Now I feel better -- it might just work fine the way it is. Tiny current from the volt-ohm meter is going through the bridge through all the coils and giving me a test resistance of the stator. Like to give me a heart attack -- I thought I was screwed.
Now for the charger connector. Only trick here is to figure out a way to strain-relief the wiring real good as this is the one that is going to get yanked on all the time. Stacked heat-shrink tubing made up an interference fit to the cable for good strain relief while insulating the wire joints at the same time.

Now for a little clever touch -- I preserved the ability to use the alligator clips by reattaching them to a spare bike fitting. The 'gator clips plug in just like a bike does.
Yoda should approve, I don't have to run out and go buy another charger for them larger alligator type batteries.
So, the sun is still up and I take my solution out to the swamp to show Master Yoda. He grunts, pulls on the fitting on the charger to make sure it is firmly attached, asks me what output voltage I am getting (13.5 volts on the nose) and he asks how much it all cost, all total, which was $17.53 with parts left over to do an extra bike later on.
"Keep the change" he sez.
Well, I just about let the bike drop on the ground and my jaw with it. Keep the change ??!! Never ever before .....!!!
"Well you did -- preserving the use of the charger for other batteries. Proper use of the Force, it was. Tomorrow give you another harder test we will -- see if this excellent progress you can continue."
Whups -- another test tomorrow? A harder test than this one ??

Being a Jedi is hard, sometimes I wonder if it is worth it.