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Putting Single Trumpet air horn on my Road King. The Trumpet didn’t come with the instructions. I found something similar on line. It shows a relay and adding a positive & negative home run to the battery…
It doesn’t look like the OEM horn went through a relay, only a accessory fuse. I mean the horn button already goes through a fuse. So should I wire it as depicted?
Connect it to a battery and try it before installing it
So you’re saying if it works, I don’t need the rest? I’m not the genius I tell my wife that I am. Just wanna be sure the relay isn’t needed to keep things from catching fire..?
So it does work just using the two factory OEM wires… but I’ll try a beefier wire because I think the power is held back. It’s kinda half hearted at a high pitch, stops and switches to a low pitch… either it’s crap, or it it “Needs More Power” - Jim T. Kirk
Guess I’ll make shift the diagram and see if it is suddenly MORE.
I think it’s gonna look ok, I needed to beef up the bracket to the fans anyway and I’ll kill two birds at once and hide the support to the fans under the horn. Just hate the complication of another wire to the main breaker… oe worse the battery terminal. I like is simple and clean.
Freakin fans are needed but they are a pain. I’ve gone through three factory horn brackets. Last one I made out of 1/4 thick steel and it too after about 4,000 miles cracked and broke.
Yes, use a relay to supply battery power to the little compressor.
The oem horn doesn`t need a relay because the current draw is very small.
The blue and white wires in that pic are not the power wires of the relay, they are the control wires.
When the horn button is pressed, a small amount of current will pass through the blue wire, through the coil inside the relay, and back to ground via the white wire.
When the coil is energized, the switch in the relay closes, allowing current to flow from the battery, through the red wire, across the relay internal switch, into the compressor and then back to ground via the black wire.
Using a relay will not only provide sufficient current to the horn compressor, it will protect the switch, which is not designed to supply the amount of current used by the compressor.
Yes, use a relay to supply battery power to the little compressor.
The oem horn doesn`t need a relay because the current draw is very small.
The blue and white wires in that pic are not the power wires of the relay, they are the control wires.
When the horn button is pressed, a small amount of current will pass through the blue wire, through the coil inside the relay, and back to ground via the white wire.
When the coil is energized, the switch in the relay closes, allowing current to flow from the battery, through the red wire, across the relay internal switch, into the compressor and then back to ground via the lack wire.
Using a relay will not only provide sufficient current to the horn compressor, it will protect the switch, which is not designed to supply the amount of current used by the compressor.
Anywho.. It’s freakin Loud but not the sound I was dreaming of. Kinda like a loud moving truck or modern semi… Not that multi toned Train sound. Might have to add a second shorter trumpet to get that violin overdubbed train sound. I was after ridiculous.. sorta just sparingly for fun. I ride in packs a lot and it would be a convo behind the Busa’s.
It’s gonna look cool kinda tucked in between the shift linkage and the fans. definitely needed the relay and direct current. Actually wondering if heavier gage wire would help.
I’m seriously looking into adding a coil and plugs to my tail pipes…
Anywho.. It’s freakin Loud but not the sound I was dreaming of. Kinda like a loud moving truck or modern semi… Not that multi toned Train sound. Might have to add a second shorter trumpet to get that violin overdubbed train sound. I was after ridiculous.. sorta just sparingly for fun. I ride in packs a lot and it would be a convo behind the Busa’s.
It’s gonna look cool kinda tucked in between the shift linkage and the fans. definitely needed the relay and direct current. Actually wondering if heavier gage wire would help.
I’m seriously looking into adding a coil and plugs to my tail pipes…
The current draw from the compressor will dictate what size wire is necessary.
Train horn wiring advice
