accessory horn

[williamemack]

I ended up ordering the Freeway Blasters and relay from Aerostitch. I don't anticipate any trouble with installation, but you'll hear from me if I run into a snag.

Will

[Rob Valdez 79 R65]

Cool!  I think you will be happy with their performance.  Be careful of your ears if you try them out in the garage.


Mine came with gold-colored metal mounts that also act as the ground.  I didn't like the bright metal, so I taped off the ends and spray-painted them flat black.

You have to tape off the ends to maintain the ground path, if you do this.

[trolle]

The Fiaam Blasters are less complex than the air horns, so I like them for that.

Please don't let the idea of a relay scare you away.  That relay is what gives you the power to make a lot of noise.  It is basic physics that cannot be ignored.

And it is not that hard to hook up, and we will help you through it.

As I have purchased a set of Fiams for my rebuilt I would appreciate your help, which relay and how to connect?

greetings from a relatively warm north

[drewboid]

One commonly available relay (in the states) is the Radio Shack 12 volt automotive relay Model: 275-001.
there are four terminals - 85, 86, 87, 30.  Unless your horn came with, one pick up an inline fuse holder with the red wires attached - Radio Shack has several; as long as it is over 10 amps rated you should have no problem.  Use the hookup wire that came with the horn or #10AWG.

Connect the two wires presently going to the horn to terminals 85 and 86. These are the relay coil terminals - polarity does not matter.

Connect one end of the fuse holder to the + of the battery and the other end to terminal 30 of the relay. Connect a wire from terminal 87 of the relay to one terminal of the horn (+ if it is marked such, usually it only matters for air horns). Connect the other horn terminal to a GOOD chassis ground.

Make sure there is a fuse in the holder, put in your earplugs, turn on the ignition, and push the horn button.
"CAN YOU HEAR ME NOW?"  

[williamemack]

If you are installing a pair of horns, do you wire them in parallel or series? I bought some 14ga wire today for this job. Is that going to be insufficient? Where is it best to mount the relay? Room for any of this in the fuse box area? And finally, do coiled trumpet style horns need to face downward to keep from being damaged by debris?

Thanks guys,

Will

[nhmaf]

Wire the horns in parallel - the power line should run to the same terminal on each of the horns and depending on whether the ones you got have a separate ground terminal or just ground through the mounting bolt the grounds just have to get to a good electrical frame connection.

14 AWG should be fine for the horns.

Point the trumpets generally downward so that they don't fill up with rain water and grit !!!   They don't have to be exacty straight down, but should be pointed generally down and either to the rear or to the side for sound dispersal (.ie don't point the trumpets inward toward the center of the bike and each other - they'll still be pretty loud, but won't project as well).

Usually there is space for mounting an extra relay or two on the relay bracket that is under the fuel tank, where the other relays are.   It keeps things all in one place, tidier, and generally out of most of the rain, etc. and usually in a path from the battery up toward the horns mounted on the front of the frame.

[Lucky_Lou]

I get the impression that 1980 R65s may have come with horn relay. I don't have a wiring diagram. I suppose if I were to disconnect the horn and then push the horn button I should hear a relay "click" if I have one. BMW offers a OEM second piched horn as an option. I may use that as the Supertones color and size would negatively affect the "naked" character of my baby. Same for Freeway Blaster.

mine has no relay its a 1980 i may fit one though to fit a differant horn or buy a cowbell
Lou

[montmil]

I get the impression that 1980 R65s may have come with horn relay. I don't have a wiring diagram. I suppose if I were to disconnect the horn and then push the horn button I should hear a relay "click" if I have one. BMW offers a OEM second piched horn as an option. I may use that as the Supertones color and size would negatively affect the "naked" character of my baby. Same for Freeway Blaster.

mine has no relay its a 1980 i may fit one though to fit a differant horn or buy a cowbell
Lou

Lucky, relays are simple to fit and really do increase the performance of whatever electrical accessory you're adding. They also reduce the electrical load through the switch -and wiring- which, in turn, will make the switch last longer.

There are a number of sorta "universal" relays you might use. Suggest you tell your auto bits clerk what you're doing and see what they recommend. Beep Beep

Monte

[Rob Valdez 79 R65]

I mounted mine where the old horn was.  I can still remove the front cover with no interference.





I mounted the relay on the bracket that the T.S. beeper used to mount.  If your bike never had a T.S. beeper, you may not have this tab on your frame:


click for larger

[williamemack]

OK you use the OEM wires to the OEM horn to activate the relay and do you go all the way back to the battery to get the power or is there another suitable source under the tank? I gather you take TWO leads from the relay, one to power each horn. I have some 14 GWA wire for the run from relay to horn. Do I need larger (10 or 12) to run from battery to relay?

Thanks again guys.

Will

[nhmaf]

You can use the original horn wire from the button to run the relay.

You should go back to the battery with the 14 gauge wire to get the power.
If you use multiple 14 gauge wires from the battery then you should put an inline fuse in each one.
But, given that you probably won't be beeping the horn on a continuous basis the brief periods of  8-12 Amp current draw
from those horns won't cause much of an issue at all with the 14 gauge wire and only a few feet in length that it is from the
battery->relay and relay->horn.  I think that you're fine with a single 14 gage wire, with inline fuse.  Don't bundle it/tie-wrap it tight
with other wires all the way along the path, but do use tie wraps to keep it neat and tidy, etc.  

If you want to be super-duper safe, you could go to 12 AWG wire, but that is probably  the largest that you could get and still use the same connectors as the 14 AWG to connector to the tabs on the relay or the horns.

[Semper Gumby]

If Fiams from Pep Boys wont do it for you, you can always try a set of these!!!


http://www.howardshorns.com/  

[Rob Valdez 79 R65]

The positive wire from Terminal 87 is a 'Y' - leaving 87 as one wire, then splitting into two, one for each horn.





from: http://www.boxerworks.com/phorum/read.php?f=1&i=243289&t=243185#reply_243289

[trolle]

Thank you Rob

Now I will go and do the rest of the cleaning up. I have found the perfect remedy for cleaning, one that really works without destroying anything. I am sorry that I cannot tell you the formula, but I think it is based on phosphoruos acid and it contains some inhibiter preventing it from attacking the metal.

greetings from a stormy and wet north

[williamemack]

I finally finished installoing the horn this afternoon. I ended up buying a 420hz BMW horn to add to the OEM piece. The wiring was straight forward thanks to this forum's aid. The only decision was where to mount the relay (used empty space on sheet metal holding other relays under tank) and where to get a good ground (used an empty threaded hole on the same piece of sheet metal. Sounds very German ballsy.