I have a 2014 Ultra Limited. I installed the Motohorn using plug n' play and the horn was not working consistently. I then got the relay kit, but having issues installing. Has anyone installed the horn using the relay kit? If so, is there a straightforward way to do this?

 

Maybe the answer lies in one of these threads:

https://www.hdforums.com/forum/gener...n-install.html

https://www.hdforums.com/forum/elect...installed.html

https://www.hdforums.com/forum/elect...-thoughts.html

https://www.hdforums.com/forum/touri...-motohorn.html

https://www.hdforums.com/forum/tri-g...track-2-a.html

https://www.hdforums.com/forum/gener...horn-crap.html

https://www.hdforums.com/forum/touri...tra-glide.html

https://www.hdforums.com/forum/2014-...ack-horns.html

 

I have both the Motohorn "dual track" electric and the trumpet air horn on my 2008 Electra glide and my 1983 Honda Magna V65.
The wiring diagram Motohorn gives you when you buy rheir relay describes it well - but...
even though they have a fuse in the relay. if you locate the relay away from the battery like I did (it's under the HD horn cover with the little compresser) you must put another fuse very near the battery on the positive wire.
So if that wire ever loses it's insulation and contacts the frame your bike doesn't burn to the ground.
The relay is absolutely necessary - My two electric horns alone would work without the relay but were much louder with it. And adding the air horn without the relay it wouldn't work at all. All rhree work with the relay.
Good luck finding a good position to mount the trumpet if that's what you have.
My first attempt parallel to the ground kept hitting my left leg when I put my foot down.
I ended up buying a couple of nice clamps to the down tube with mounting holes for the horn.
It's forward of the electric horns pointing at the ground now.
Very loud,! it does get the smart phone enthusiasts attention.
I wish it was even louder but the only way to do that is a big air canister.

This works and it is unobtrusive.

This hit my leg and vibrated too much.