Yet another R12RTW horn mounting option

[mneblett]

I have a pair of BMW (Fiamm-style) hi/lo horns I removed from my K16, including the relay and corresponding BMW connectors. I previously had removed the K16's pathetic horn and used a BMW connector to wire the OE horn's connector to control the relay that passed power to the hi/lo horns (I'll be doing the trigger differently on the RT, more on that later).

 

Like everyone else, I've been struggling to find a "good" location for the horns. Here's what I ended up doing:

 

Under the left nose side panel is the outer wall of the air duct to the left radiator:

 

 

There is an inner wall behind it which channels ~1/3-1/2 of the incoming air to the radiator (the rest comes in by the forks):

 

 

 

 

Inside of the outer duct wall:

 

 

I decided to mount the horns between the outer and inner walls of the duct, high enough to avoid major blockage of air to the radiator and to keep them up out of the majority of the weather. The horns are bolted to the outer wall. The front horn required trimming of the bell to clear the inner duct wall. The rear-most horn is directly below the left engine air intake "snout," but does not block flow into the intake:

 

 

 

The two white spots below are the nuts/washers holding the horns to the outer duct wall:

 

 

Looking up from below, front horn at top of picture, rear at bottom:

 

 

Front horn looking upward from the front:

 

 

Closest point of approach of the rear horn to the radiator:

 

 

View of the radiator from the fork area -- essentially no flow blockage to the radiator:

 

 

For wiring, the horn wires come out of the top of the duct and run to the relay, which is mounted to a convenient T30 Torx bolt (dead center in the picture below, above the radiator). The power/ground/trigger wires go up over the coolant hoses (out of contact), behind the left intake tube to the left throttle body, to the region by the left fuel tank mount.

 

 

The upper bolt of the tank mount is a good place for a ground -- 0.0 ohms to the battery ground:

 

 

In sum: horns mounted in a hidden, weather protected, and no-impact-on-engine-cooling location. No question a bit of a pita to get to, but I already had the bike disassembled for fairing panel painting and other wiring running (requiring removal of the tank).

 

As for triggering the horn relay, instead of removing the stock horn and using the signal on its harness, I am going to see whether the Clearwater Lights' aux horn output on the Canopener 3 module will control the horn relay when the bike's horn button is pressed. If as I expect it does, I'll have three horns and no "horn error" stored in the bike's computer when it doesn't detect the presence of the stock horn.

 

HTH someone. Happy to answer Qs.

[Rob L]

Nice job. The dual horns are definitely better than the single wolo air horn that I used. I may change to this in the future. I never thought of placing them inside of the radiator shroud.

[Francis]

Is there room in there to mount short air horn trumpets and the air compressor some other place near by? I like air horns as I believe they push the sound out in front of the bike further than electrics.

[gordiet]

I just installed a single Piaa in place of the oem . Very loud!

 

GT

[eej1]

I often think about adding a louder horn. But I never use the one I have. For some reason I just avoid others rather than try and make them aware of where I am with noise. I have the extra brake light, bright jacket, but hardly even know how to use the horn. Kinda odd.

[TJRL]

I often think about adding a louder horn. But I never use the one I have. For some reason I just avoid others rather than try and make them aware of where I am with noise. I have the extra brake light, bright jacket, but hardly even know how to use the horn. Kinda odd.

So, I suspect that when/if there ever comes a time that you do need to use the horn you will really want the other driver to hear it!! That would be a bad time to think "oh I wish I had upgraded the puny OEM horn".

 

Over here; extra daytime running lights (Motolights), extra (flashing) brake lights (Hyper-lites), a rear-guard fog light, bright HiVi jacket and advanced rider training are still not enough to guarantee that a good horn is not needed. In fact our advanced rider training teaches that using the horn before starting some manoeuvres is a requirement e.g. when about to overtake a lorry that was parked in a narrow side street of an industrial estate with a limited field of view.

 

Which all goes to say, I have upgrade my 2014 F800GT and 2015 R1200RT's horns, but to each his own!

 

 

PS - One of our Bike Mags (Ride I think) recently ran an article on how to wire up a louder horn via a relay as a good upgrade for almost any bike and then the next issue had an editorial along the lines of: "Why are people upgrading their horns? The standard horn on all bikes is fine, does not need making louder and most people never need to use a horn anyway!".

[eej1]

Good points, no doubt a loud horn used at the right time could save your life. I should add it to my bike. And practice using it. And try and restrain from honking at people texting and driving as I pass by them on the freeway. That's when I have been most tempted to try and find the horn. A good loud one might even be a good idea then.

[TJRL]

... That's when I have been most tempted to try and find the horn.

Oh no what have I done? Eric with a loud horn - could be BAD!!