GT: Installing a Stebel Nautilus Airhorn
Here is my installation of a Stebel Compact Dual Airhorn in my 2006 Vespa GT200L, Lenore.

Disclaimer: I did break a nail during this installation. I used the wire cutters to trim it. This is not for the faint of heart.

So, first, my observations:
I don't take things too lightly when my darling Lenore is in question. So I did a great amount of reading posts and tutorials about this airhorn before deciding I could master this in my own. My method was overkill - and ol' chick can do this.

During my observations, I want to point this out: This fit for a Stebel Airhorn on the Granturismo is tighter than any other Vespa model. There is a ton of room on a Vespa LX. Lots in a GTS. NOT lots on the GT. Oh Piaggio - why do you do this to me?

Here is what you need to buy:
Stebel Dual Tone Compact Airhorn - California Sport Touring
Lots of product specs here too: http://www.twistedthrottle.com/trade/productview/2137

MATERIALS (not included with horn):
- 14 to 16 gauge automotive wire, 10 ft - 20 ft length (more than enough)
- 2 splice-in wire butt connectors (blue plastic variety)
- 6 female blade-style quick disconnects for same gauge auto wire (Radio Shack 64-3049)
- 1 ring connectors for attachment to battery terminals
- 1 in-line fuse holder for 20 amp automotive fuse
- 1 20A 32V blade style fuse
- weather resistant electrical tape (or use weather-sealed heat-shrink connectors)

Here we go: First, remove every conceivable screw; from the horncast through the leg shield.
Here are excellent instructions for removing the horn cast (smorris)

Here is a Clever Bastard DIY tip for you:
Grab up your empty medication bottles; peel off the damning evidence of all your illnesses by removing the labels; using a Sharpie, label the screws you've removed and close 'em tight so you don't lose shit.
{This idea was inspired by the many years of watching my husband lose shit when he does these kinds of projects. And his many medications for being married to me.}



Got every screw out? Even the one in the glovebox? The two inside the horn cast? The four at the base of the legshield? Good. Now, gently wiggle the crap out for the glovebox to loosen it from around the ignition and steering column.
Remove the cap over the coolant, careful not to drip, and you try this lift/tug/pull/cuss combo and the glovebox will come off.

The wires can all be disconnected. The Electric seat latch and main fuse box are easy. The assembly for the manual seat latch is tricky. With needle nose pliers, you can slide the large crimp out through the left side to release it, then pull the head back.


Remove the anemic stock horn. I also removed the bracket that it attached to in order to create more room for the giant Stebel.

Using this INCREDIBLY useful thread, I found the best place to jam my horn and the best wiring diagram to follow. Thanks, guy named Pierce who drew it.



At this point, the zip ties are not too tight, because I still need to finish my wiring. Keep in mind that the horn should not be mounted at an angle exceeding 15 degrees vertical. Try to keep it as upright as possible.







Here we go; onto electrical!
When I went to Napa for the wire, I was reaching for the red color 14 gauge when the manager-guy asked me, "But, wouldn't you rather have purple?". I guess that is because I am a girl. Yeah. Then I embraced the girlie in me and got florescent zip ties, too.

I have attached 14-gauge automotive wire to 2 x 14 gauge female blade-style quick connects. Do this by stripping a quarter of an inch off wrapper off the wire, stick it in the hole and crimp the holy hell out of it from each side. I have also used heat-shrink over them (that a kinda' rubber tubing that shrinks around the wires when you use a lighter on it).


I have connected those two females to the leads off of the bottom of the horn. With my Sharpie, I marked on the wire which was positive so I wouldn't forget. These are the purple wires you see below.

The red wires in the picture are coming from the In-Line fuse holder. More on that in a second.




I have attached a length of 14-gauge automotive wire to 1 ring connector and threaded the remaining length through the steering column.



I used butt connectors appropriate for 14 gauge wire to connect the wires of the fuse holder to the battery lead.

As you can see, I had even gone so far as to mark the correct attachment points on the horn relay in black sharpie on each side, so I couldn't have a blonde moment and not be able to read the face of the relay.



I brought all the wires though and connected everything and pressed the button:
WHAAAA WHAAA.
I pressed it about eight more times (be sure to check for vibration), and by that time all my neighbors had come over. Frowning.


Lastly, I went back over every inch and zip tied everything tightly and checked all my other connections.

This horn is LOUD. This is no nice-way-to-great-your-friends-on-the-sidewalk-with-a-"toot-toot". This is a fight-for-your-life-battle-on-the-highways-commuters horn, which is what I need it for. There is no doubt that this horn will increase my odds for survival on the San Diego freeways I travel daily. So, if you have a daily need to scare motorists, neighbors, or water buffalo - this is the horn for you.



So, that is it for DIY corner with Clever Bastard.
When you think you can't or even that you shouldn't try ... just get clever about it. Bridge the gap, ya know?




[original forum post by buglake]
Last Updated Tue Nov 18, 2008 12:59 pm

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