Honda 400f four switchgear advice

[10tenmen]

Hi all my 1975 Honda 400/4 is a us import that has the always on lighting which I want to change to the uk type with on off switch, I understand that I need to find a way to power the lights differently anyone any advice I have a volt meter to check feeds via the ignition but just checking before I get started. Thanks.

[Bryanj]

Just fit the UK rh switch and all will be ok

[10tenmen]

Just fit the UK rh switch and all will be ok

Lol thanks just trying to work out how to get the power to the rh switch as I have three extra wires.

[Bryanj]

If you study the UK and US wiring diagrams you will find that the US model has a "link" wire between, from memory, brown and brown blue that will be two of the connections after you remove the link. The power to the light switch is on the black which also feeds the starter button and kill switch.
I dont have the manual to hand but there is a download one on here that will have the wiring diagrams in for you to study

[mattsz]

10tenmen - I don't know where we left this conversation in the US forum, since it's down again...

My wiring diagrams are only as good as my source material... but I've made up PDF ones for both the US and UK models.  I started with the US model, then modified it to make the UK changes.  As a result, it's an interesting exercise to open them both in a PDF viewer, zoom and scroll them to the same magnification and position (in this case, the upper left corner of each diagram is where the headlight switch info is), then toggle your view between them and observe how only what's different between them changes.  Could be useful for you...

I've attached them below...

[10tenmen]

If you study the UK and US wiring diagrams you will find that the US model has a "link" wire between, from memory, brown and brown blue that will be two of the connections after you remove the link. The power to the light switch is on the black which also feeds the starter button and kill switch.
I dont have the manual to hand but there is a download one on here that will have the wiring diagrams in for you to study

Thanks I have the brown and brown blue from the fuse block into the loom but from there I can’t find the link checked the front light bucket and the right side connections still no joy ?.

[Bryanj]

Believe me they are in there or your headlight would not work.

[mattsz]

Bryanj is right, of course.  The question is, where is that connection?  I did some digging and found mine burried in the big bundle o' connectors on the left side of the frame just beneath the tank's rubber mounting disk.

The thing is, some of the wiring diagram's "dual-colored" wires on my bike ('77 US spec) aren't actually dual-colored at all - they're solid colored with small bands showing the secondary color, but only near their ends.  I believe the "link" in question is wired this way.

I've got a solid brown wire which appears out of the loom with an insulated bullet connector that's blue instead of the usual clear - coming out of that connector is another solid brown wire, but with a single blue-colored band as I described.  A short way from there (one inch, maybe?) the brown wire connects to a black wire beneath what looks like a small wrapping of black electrical tape, and that black wire joins up with other blacks in a bullet connector cluster, just like in the diagram.  I'm guessing this brown-to-black taped connection is the "link" in question.  My suspicion is borne out when I look to the fuses - a brown/blue wire runs from the fuse block to the connector, but on the loom-side of that connector, the wire is solid brown... with a blue band.

Here's a couple of photos (click to enlarge):

Connectors beneath the tank - brown wire from loom to the blue insulated bullet connector, indicated by the red arrow.  Continue to follow the brown past the little blue band to the "link" indicated by the green arrow - it's black from there to the black connector cluster.

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Here's a pic of the fuse block's connector - solid brown wire with blue band indicated by red arrow:

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All that said, I have no idea if your US import bike has the same wire color idiosyncrasies mine does, but I'd bet a dollar that you'll find the "link" in question right there...

[10tenmen]

Ah all becomes clear I have the brown wire in the blue sheath but no link wire so I think mine has been bodged somewhat so my headlight is getting power elsewhere I think, I can get a replacement loom for £80 so may do that. Thanks for the photos they helped a lot.

[mattsz]

My pleasure - glad my bike is good for something!  Good luck!

[10tenmen]

My pleasure - glad my bike is good for something!  Good luck!

Right so I now have lights working via the switch, my tail light is still on with ignition so that’s my next fix lol.

[10tenmen]

Thanks to everyone it’s alive all lights now working it turned out there was a permanent ignition live to the rear light I simply Re connected and it’s now working via the switch, I had to email Davis Silvers for the switch wiring diagram as the colours were slightly different, I fitted new throttle cables to the switchgear and it’s running sweet now waiting for dvla to give me a reg number so I can get out on it.
Great forum thanks all.

[mattsz]

Thanks to everyone it’s alive all lights now working it turned out there was a permanent ignition live to the rear light I simply Re connected and it’s now working via the switch, I had to email Davis Silvers for the switch wiring diagram as the colours were slightly different, I fitted new throttle cables to the switchgear and it’s running sweet now waiting for dvla to give me a reg number so I can get out on it.
Great forum thanks all.

Would you mind forwarding that DS wiring diagram to me?

[10tenmen]

Attached as it came hope it assists thanks Gary
Our technicians who refurbish our CB400F projects have told me that ;

Black/brown wire in right switch goes to brown/ blue on harness . This brown/blue harness wire is all brown with a blue cover over the end terminal.

Black/yellow on l/h switch goes to black/yellow on harness .

Black /yellow on right switch goes to a black wire on harness with multi socket on end .( 4 female sockets)

[mattsz]

Attached as it came hope it assists thanks Gary

So it's just that description and not a pictorial diagram then?  Ok, thanks!