Topic: 1969 CB750K0 headlight wiring

[34barab]

Bike is a 750K0. Trying to reattach headlight wiring after having headlight bucket repainted.  So far, all but TWO WIRES are attached and all electrics work: frt and rr winkers; hand and foot-activated brake light; headlight hi and lo beam; electric starter; ignition switch positions (off/ign/park light); speedo/tach lights; beam, flasher, oil, and neutral jewels.  RH switchgear includes off/low/hi beam switch, starter button, ignition cut off switch.  LH switchgear includes left and right turn switch and horn button.  With engine off and ign switch in start position, everything works.  Bike not running yet, but I'm not sure it would have any effect on functionality.

In the headlight bucket, the TWO WIRES in question both come out of the main harness.  One is a single solid brown with a sgl female connector, and the other is a single br/wh with a triple female connector.  These are visible in the attached photo at approx 6 o'clock on the bucket.  Also shown is a multi br/wh connector a little left and up from there, with one open female connector.

I think from other posts that Honda included the single solid brown wire, but it was only used on non-US bikes that had a pilot light(?).

More concerned about the two br/wh multi connectors.  they both have one open female connectors, so I was wondering if they should be connected to each other?  I have the color wiring diagram for a 69 - 70 CB750K0 available on this forum.

[jakec]

I'm pretty sure those are for an accessory. so the solid one is power, not sure about the striped one. But you can leave them as is.

[Don R]

 Brown is for a front parking lamp. Brown / White is for any light that comes on with the headlight switch, dash lights, running lights on newer bikes, etc. There should be an unused green female or two also.

[34barab]

Brown is for a front parking lamp. Brown / White is for any light that comes on with the headlight switch, dash lights, running lights on newer bikes, etc. There should be an unused green female or two also.

I rechecked all the green wires coming into the bucket and they are all connected.  Wiring diagram shows two greens coming into the bucket from the main harness, each ending with a multi bullet connector, check, and then five greens branching off from the two multi's.  One of those attaches to the speedo sub-harness and one to the tach sub-harness.  Two more greens go to the winkers and one to the headlight.  There is no unused green female connector in the bucket; there is an unused green female spade connector exiting the main harness right behind the starter solenoid. 

Full disclosure, there are two single unused wires in the RH switchgear sub: one solid yellow and one yellow with white stripe.  They have been clipped just below the end of the plasticy (word?) sheath protecting that harness.

Any thoughts?

[bryanj]

Yellow and yellow white are usually found on a 450 as part of the charging circuit.

[34barab]

Yellow and yellow white are usually found on a 450 as part of the charging circuit.

Since all the electrics are working properly, I don't want to mess things up.  Just trying to get things right.  But...…..I am curious about the unused yellow and y/wh wires.  This bike was "restored" in 2005.  Is it possible that a CB450 harness was used.  I have not looked at that wiring diagram.

[HondaMan]

For the Yellow and Yel/Wh wires, look in the Police Bike wiring harnesses or the Japanese-only versions. The Japanese 1970 bike had a "you are going too fast" light in the top of the headlight shell (I don't remember the speed) that came on when the rider broke their law. The Police bike (one that I remember) had 2 extra light wires in the circuit, one for radio power and likely one for the red light.

The Brown/White wires are for lighting circuits, like taillight and instrument lights. The late K0 and early K0 sometimes had 4 of these coming from the instruments, later ones wye'd those together in the instruments (for one each), leaving 2 open females in the headlight bucket.

[bryanj]

The 450 switched in extra coils in the alternator when you turned the lights on and its possiblr somebody fitted a 450 disc brake switch (fork sliders were 750, legs slightly shorter) and just cut those wires as they are not needed, all they do is joint together when lights turned on so no problem just sat there