Topic: '72 CB500 JDM Speed Warning Light

[Dr. Frankenstein]

I'm rewiring my 1972 JDM (Japanese Domestic Market) CB500 Four and it has a speed warning light mounted in the neck. I'm pretty sure I have everything connected correctly, but there is a male brown/red wire and a male black wire coming off of it that I'm not sure where it goes. I have the correct wiring diagram for a CB500K, but I'm not seeing a brown/red wire connection anywhere.

The only connection I have in the headlight bucket that is Brown is a single female connector that I believe fits the brown male connector that goes to the little light that (for some reason) is mounted in the headlight that you can see in the pic. Any idea where that Brown/Red wire for the speed warning light goes? (And yes, I've repaired all those open wires).

[HondaMan]

You might not have the little module that makes the light go ON at 50 MPH (or thereabouts). I have a JDM-equipped CB450 in the garage, will try to take some pix later today.

[Dr. Frankenstein]

Ah! That could be! I took a lot of pictures, but don't remember it being attached to anything...truth be told, this bike was in pretty rough shape electrical-wise...I'm pretty sure the wiring under the seat isn't supposed to be like this...! HM, you don't happen to have a 500/4 JDM wiring diagram, do you...? And what's the function of the little light in the headlight?

[bryanj]

The little bulb is a "sidelight" and is a requirement in some countries, should also turn on with rear light when ignition key is in th P(ark) position, also a requirement in some countries.
The unit to make the speed light work i think is by the coils and the speedo has extra wires to make it work