The battery on my Harley goes dead if the bike sits for a few days. I think I have a short or something in the head light circuit, which I modified to installed a flashing modulator. Probably a bad connection allowing + to ground? How do I isolate, so I can eliiminate the problem? Would a sharp point test light find it? I kind of know how to use a multi-meter, at least for resistance and voltage, not so sure for amperage. Any insight would be appreciated.

I rembember haveing a hard time with my electrical on my FXRS. All of my problems were in the head light bucket. Conectors come lose, wires rub, I had to be very caerful how I laid the wires into the bucket. I had to redo it several times. They make trickel chargers for them, but your drawing it down to fast for that. I hope this helps.
I miss my Harley.
Joe

Most multimeters have a ten amp test circuit connection. Place the knobs in the ten amp test position, hook up the multimeter between the battery negative and the frame. See how many amps are being drawn. Start unplugging various componets, see it the amps drawn changes, when it does change, that's where the problem it.

Oh yeah, when all else fails, read the instruction manual for the multimeter, lol. I've never done that, take care, Don

Don nailed it! You have a short to ground. You can do it with the test light also. When the light goes out, bingo.

I had this problem last year, but it went away later in the summer. Don't think it is in the headlight bucket as I just had the dealer install a new one. I guess I'll start by re-doing my connections where I cut into the harness to install the modulator.