Rebuild Honda CB 750 F1 electrical wiring issue

[Tony62]

I am rebuilding a CB750 F1 and have bought replacement digital clocks but I have having an issue wiring these up. Any hints? This is a single horn model, the issue I have is the 3 switch position (ignition off, park, ignition on) and getting the clocks to work. I can see how to connect the earth, live but not the 3rd lead (12+)

Has anyone done this and can you advise me.

[Bryanj]

One of the lives will need to be "Permanent" I.E. from the red at the switch; the other live will need to be "Switched" I.E. from the Black at the switch, you will have to sort out which is which from the instructions. Green in the loom is earth.

Should you remove the battery blow a fuse and/or it drop below a certain voltage the clocks will loose all their "Memory" and settings which is a pain and why they ain't used on bikes that often

[Tony62]

I have connected according to the instructions, however, when key is in the on position, there is no switchable live. It is the original loom for the bike, and I can't identify the switchable "Live" which is normally the brown wire which doesn't work. If the ignition is turned to Park, the clocks work.

[Spitfire]

Hi Tony, there is no "magic bullet", when I rebuilt mine I had a duff ignition switch and had to replace it, then despite cleaning every electrical connector on the wiring loom (WD40, Dremel, Brillo pads, dielectric grease etc) while it was off the bike, I still had a problem with power to the rear light, in the end I had to trace each wire and connection using the wiring diagram to get everything working. It can be a bit slow, as to digital clocks that is nuclear physics to me!

Cheers

Den

[kifer]

Would go for belling wires out as per diagram, jot it down for future ref. just don't have wiring to digital clocks connected when using multimeter

[Tony62]

Thanks for all the help. Issue now resolved, black wire was switchable +ve, once I'd accounted for tat and checked connections, everything works as it should.