Question edited for a lot more clarity, full 'year make model'.Question moved to model category.Harley Davidson has a beautiful wiring manual, but they only show 2 pages!This is partial diagrams. The HD Forums are great.https://www.google.com/search?q=2004+electra+glide+classic+rear+lights+wiring+diagramService Manuals are a better way if you are keeping the bike.https://www.google.com/search?q=2004+electra+glide+classic+wiring+diagram+pdf..
Hi, Louis and the usual suspects are:
1. Excessive electrical "HEAT" aka "AMPERAGE" melts the varnish insulation causing the coils to short out.
2. Overheating due to a faulty voltage regulator.
3. Voltage regulator not properly grounded.
4. Loose rotor magnets or stator bolts.
5. Faulty starter relay.
6. Old battery dead cell loose or corroded cables.
7. Faulty wiring in the charging circuit.
8. Excessive wattage in a batteryless system.
9. Aftermarket parts are usually substandard.
10. Headlight not designed for a motorcycle system.
Some bikes have charging systems that get the job done but just barely and will have the most failures, you can upgrade the system with quality parts and higher output. Relocating the voltage regulator to a spot more conducive to airflow will help immensely. Regular wiring system checks for corrosion chaffed wires, rerouting harnesses that run too close to heat sources ie. cylinders-exhaust etc. is great preventive maintenance to avoid those breakdowns in the middle of nowhere at 2 in the morning.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below and for more specific information or questions at no charge please feel free to contact me at [email protected]. Good luck and have a wonderful day.
https://www.youtube.com/watch?v=WpzLngaSJNQhttp://www.mediafire.com/file/trwd3nr1nlgb2ky/2001+Harley+Touring+Service+Manual.pdfhttps://partsfinder.onlinemicrofiche.com/ronnies/showmodel.asp?make=hdmchttps://www.harley-davidson.com/us/en/owners/motorcycle-maintenance.htmlhttps://www.6ya.com/
SINCE THERE HAS BEEN REPAIRS MADE; CHECK IF ALL ENGINE TO FRAME CONNECTIONS ARE TIGHT.
ALSO, WHEN THE BIKE IS ON ITS CENTER STAND; GRAB THE LOWER END OF THE FORK, PULL AND PUSH TO SEE IF THE TRIANGLE BEARINGS ARE TIGHT.