Installing a new horn and blown fuses

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MajBach

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Update 2 : Disregard the following, I've figured things out and installed a relay. Thanks

So I am currently replacing the horns on the bike to a beefier air driven Strebel type. I considered breaking apart the two components of this unit (compressor and horn/bell) and mounting them where the factory horns are installed and connecting them with a flexible air line. After lining things up however I decided to mount the unit whole on a piece of flat bar in front of the rad.
I bought a thin piece of metal, curved it to follow the contour of the rad, fastened it to the frame where the factory horns mount and mounted the horn in the middle in a horizontal position. This minimizes interference with the airflow and ensures the horn wont contact anything when the forks are compressed.
My intention was to run each pair of original horn wires to the new horn and Y then into one (to split the load) rather than installing a relay. Once I had the horn mounted I wanted to give it a quick test with one of the leads and was surprised to observe that the moment I touched one of the leads to the post, I got a noise (the polarity was wrong for the horn – but I didn’t know where the power was coming from); the ignition was on. I couldn’t figure this out so I took the same two leads and experimented with them on one of the stock horns. Sure enough, there was a point where one of the leads was hot and the horn blasted when I grounded the free lead of the horn to the frame.

I had to stop there for the day.

Upon return today, I somehow managed to short the horn out in the process of trying to make sense of this. Now, when I turn the ignition on, the ABS light slowly flashes and of course the horn doesn’t work nor does the windshield. I cannot figure out which fuse controls them (it isn’t in the fuse boxes, is it? The manual doesn't state where).
Once I get that fixed, why am I seeing a hot wire to the horns? The only way I can figure eliminating this if this is indeed the norm is to somehow ensure the new horn isn’t grounded to the frame (or I suppose use a relay?).

Help.

Update: So I figured the fuse is the 15A for the signals.

Update 2 :

 
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A mate had some problems with his Gen 1 circuit recently.

The horns are switched on the negative side, so there is power there as soon as the ignition is switched on.

Be very advisable to use a relay, the stock wiring is rather small.

 
Relays all the way to Aux horns or lights. Directly wire your load circuit to the battery (fused) and the control (low voltage) side of the relay to the OEM horn connector. No/slight load on the OEM harness. Less risk of releasing the magic smoke.

 
As stated previously, use a relay. I just did this install a few months ago and it was not hard. I mounted the relay right where the right stock horn would be and just plugged in the factory horn wires to the relay to operate it. Then ran a (+) wire from the Batt. to the relay and from the relay over to the horn. works great...

 
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