I have just bought a three relay kit for my 850's headlight and horn and one thing I don't get is the horn wire connection. The two wires that go to the horn itself I get but there is a third Black wire the diagram says to hook to the "negative" side of the horn switch. Can some one tell me in dumb person talk exactly how to do this??? Where to I make this connection? I think it would be the white wire shown in the bikes wiring diagram but where do I make the connection at? And is that the correct wire? Thanks. Glenn.
Headlight/horn relay wiring help please.
- Thread starter gtsun
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1. Is your bike still positive earth ground!
2. Where did you get this kit?
2. Where did you get this kit?
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Wire power-ground leads to horn and relay power terminals, then run a ground lead from one relay switch terminal and another from horn button power feed. Don't remember the color but easy to find which lead is on/off power. Head lights more tricky to keep hi beam flasher and normal switch function with head lamp switch. Took me a few nights to figure out that 2 relay wiring.
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gtsun said:
Only one wire should go to the horn (from relay terminal 87). As the other horn terminal wire should go to ground to complete the circuit (check your Commando wiring diagram).
So the relay switching power source (to relay 86) should be the purple/black [PB] wire (Commando 1971-'74) from the handlebar switch. (W = power "IN", PB = power "OUT") as PB would normally be the power wire to the horn without a relay.
85 to ground (ground for the relay switching circuit).
Example
Ok LAB so if I understand this correctly I go find the PB wire coming out of the horn button and conect the black wire of my kit to that. Seems rite. But why would my kits wiring diagram call that the "negative" wire? Again kit sys "Conect this to negative side of horn switch"
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If you can't get it working email me and I will try to talk you through it. LAB is right 15 AMP will do the trick. It came with a fuse but I did not check yours sorry.
No worries Greg I'm positive it will work when I get to it. I keep thinking I'll have time but fortunately things like the Vintage motorcycle races at Willow Springs this weekend keep getting in the way!! There were so many amazing bikes today... The Vincent Grey Flash that Marty Dickerson raced owned by Ken... I'm having brain freeze. A real 1971 Production Racer with 11 true miles? It was a beauty. Many Norton Manx & what I asume was a pre 1940's International. Heaven. I will try to hook up my relay's Mon Greg and will let you know how it goes. Thanks Glenn.
concours
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I'm adding relays for the headlight, I have them all wired, ran a wire to the battery (fused) and then began thinking why there is a TRIPLE wire on the earth side, and a single 16ga on the negative of the battery. I conclude the alternator power connects to the harness somewhere and there is multiple conductor to carry the current to the big ticket items, like lights, etc.. So,, I question the logic of feeding the relays from the battery, seems like it should be tapped in at the multiple conductor. Thoughts? Experiences?
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concours said:
Feeding the relays from the battery is best, the whole idea is to avoid voltage drop through the wiring and switches which causes significant headlight dimming...personally rather than HL relays am using one of the uberbright yet normally short lived H4 bulbs that die quickly (within months) on a vehicle with normal voltage but holds up fine on my Norton with a low average voltage, has been working well so far HL is very bright
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