[Prairie Hunter]

2008 Bullet 500ES---about 20 minutes into my morning ride, the bike sputters...ammeter needle twitching like crazy, going deep into the red side of the gage.  Switched off the lights, everything stabilized...ammeter needle goes to middle of the green side, and then settles back to normal.  Any ideas?

[Ice]

 Without diagnosing it in person I hesitate to say but do suspect a wire rubbed through and grounding.

[ace.cafe]

The lighting is on its own AC circuit.  Look for short circuit in that wiring circuit.

[Prairie Hunter]

I suppose that's a possibility, but here's the thing:  I'm in a situation similar to Timerunner...bike's been in storage for a few years.  I bought it new in '08 with 13 miles on it, and it has just now passed 3k.  Doesn't seem like that's enough riding to wear out a wire, though I guess it could've happened.  No real mods to the bike...replaced original fenders with 350 fenders, attempted to replace the battery with one of those big caps, but undid that.  Had to replace the battery itself--the original froze a few too many times in the South Dakota winters.

[mattsz]

Prairie Hunter... even 13 miles is enough to wear out a wire if it's out of place - so anything could happen in 3000.

[Arizoni]

PH:
As you frinkled with the rear fender, the wires going to the tail light and rear turn signals are the first place to look for a damaged wire.

This branch of the wiring harness has a nasty habit of contacting sharp metal edges which can cut thru the wires insulation.

[Hondo]

The head is AC and all the rest of the wiring is DC after it is converted.  You could disconnect the headlight circuit and see if it goes away.  One place to look for sure is behind the headlight, if the harness rides on the back of the lamp it can melt through and go to go to ground.

[Adrian II]

If I understood the wiring diagram in the Snidal manual correctly the AC lighting for the headlamp is completely independent of the DC side, including the ignition, so I'd want to check the tail light and pilot lights.

A.

[Ice]

Prairie Hunter, humor me if you will.

  Remove your points cover, take a  good good look at the wire to them and it's connection and then gently move the wire away from anything it may touch then run the engine and see if you can duplicate the symptom.