CB750F1 Wiring

[martin_uk]

Finishing my final F1 project and trying to sort out wiring.

I bought a repro wiring loom from DSS, but having trouble finding the correct wiring diagram.

Its a UK bike reg in Feb 78, but suspect earlier manufacture, as I heard sales dropped off, delaying registrations.

It has a frame number CB750F-10406xx (x to hide)

The wiring diagrams I have all show the horn switch providing an earth to horns with a switched live feed to them .

My switch supplies a live feed to horns which have a permanent earth.

[mickwinf]

if its similar to the 500/550 set up it depends which type of switch you have which does vary from US to UK spec. do you have a combined flasher/ horn button or horn only? if its horn only the power goes via a black wire under tank to one terminal of horn, then from other terminal via a light green wire to horn switch then to earth through handlebars when you press horn switch. With the flasher arrangement type you get a live feed to the switch, then when you press the horn button it connects to the light green wire to the horn terminal, then goes to earth via a short lead from the other horn terminal to the mounting bolt on the horn mounting bracket. Hope that makes sense and it is similar on the 750.

[Bryanj]

Also at about the same time the starter button changed due to the Yanks having permanently on lights, early ones earth to bars later ones send power to solenoid.