The wiring to the relays looks fatter than normal and I would assume these have been added by a previous owner. Yellow wires on these models are usually used for the supply to lighting, being parking light, clock illumination and tail light. As it is in the headlamp shell I would suspect that it is the supply to the parking light.
I think you might be right, I think the bike used to be a European Police bike and was converted before I got it. There is a ‘squeeze clip’ on the headlight parking light so it must go there.
I’ve also got a spade block with a hole in it, I wonder if it’s an earth but can’t for the life of me see where it goes. The only thing that is bolted on are two black square blocks that mount at the top but the bolt is a tad too big for the spade block. Any thought?
The new gray wires with crimp spade appear to connect to the new relays, the other wires are black on this Christmas tree of spade connectors. I assume like you, that they are all earths. If there is a drain hole in the bottom of the headlamp shell near the front they could bolt to that. Otherwise just ensure that one of the wire runs to a good earth somewhere else on the bike.
To be sure of the above let us know what number contact the grey wires run to on the relays and where the other black wire run to.
PS the two big black blocks are the relays someone has added, probably to activate the headlight and change main to dip without having large electrical currents passing through the handlebar switches. A good plan
I would run a wire back from that common earthing point back onto the frame somewhere. Relying on earthing through the headlamp shell is not good as it is isolated by the rubber mountings on the forks.
I agree with Don, but I would assume that there is already a wire back to earth as there will be one in the 15 pin multi connector, you should check for one, use a multimeter on resistance between the multi spades and an earth on the frame or engine. I personally would fix that connector somewhere in the headlamp shell to stop it moving around and potentially shorting out on other wires on a bumpy road. Double sided tape or a tie wrap would be a minimum.
Those are those horrible coloured crimp connectors I don’t like.
Yellow wire usually means sidelights, aka park lights.
I spy a yellow curly disc lock reminder in the pic. Can I mention I expensively mashed up my Ural’s front disc back in July. You’d think wheel would just stop turning so bike won’t go forward anymore? But no. Fortunately, in the event, the lock was fairly weak, just splayed apart and fell off (else who knows how much more damage), but I still needed to be RAC’d back home. As a anti-theft device, to stop bike being wheeled away or ridden (albeit with non working front brake), hopeless. I won’ use disc locks any more, instead I now prefer my second choice, cable locks. Or chains.
Thanks all for some very useful feedback, I will attach the spade block to the light shell and the loose yellow looks like it fits in the parking lamp ‘clip’.
I have had a similar issue with a disc lock in the past but this one squeezes the front brake so won’t go anywhere, however bikes are now secured in a purpose built garage with excellent security system, as well as ground anchors, chains (& disc locks).
I know if someone wants them, they’ll have them but the odds are in my favour and I can’t wait to see the cctv footage if an attempt is made.
I’ll let you know how I get on with the electrics (good or bad).