georgesmkt: the horn fell off my 85 FXRS Lo-Glide while I was riding (It is located under battery box). When it fell, it pulled out the wiring. Now, I dont kow where to go to run a new hot wire.  Only one wire is needed, the other is a ground.    Anyone know where the harness is located?

2 options.. should be a wire harness ya can access under the tank along the frame... using a test light find the wire thats hot with the horn button pressed (not hot with button relieced).. second option if ya can't find it there.. is find it where the wires come out of your handlebars, and just run a new wire from there....

Don't remember off the top of my head how the connectors are set up on the old FXR.

Not sure if this help...