Installing a Stebel Nautilus Air Horn on a BMW K1200R
As anyone familiar with the K1200R will be aware, it’s a very compactly designed bike with almost no spare space anywhere. In my perhaps irrational desire to remain alive, I was determined to find a spot to fit an air horn, but I didn’t want it hanging out somewhere where it would ruin the clean lines of the bike.
After removing every panel and cover on the bike and trying unsuccessfully to fit the thing into every spot I could think of, I finally hit on the perfect place: behind the windshield, just in front of the instruments and held in place by the “Bracket for Instrument Cluster” (BMW wording). It was so obvious, in the words of my old grandpa, “If it hada’ bin a snake, it woulda’ bit me.”
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Horn in place, windscreen removed for detail|
This spot is perfect because the horn is virtually invisible yet it’s high and up front where it can be heard, it’s well protected from rain and dust by the windshield and it’s very secure (see below).
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Horn in place behind windscreen|
The instructions say to try to mount the horn vertically, though this doesn’t seem to be mandatory.(Note: We still recommend staying as close to vertical as possible, varying by 15 degrees at most.) In this spot, it’s at about a 45-degree angle, which is not perfect, but is probably vertical enough to allow the horn to work reliably. When I initially found this spot, I was concerned that there was no way to use the standard mounting bracket and I was thinking that I’d have to fabricate one. Then I thought, “Hey, this thing just jams in here snug as a bug in a rug.” I removed the Bracket for Instrument Cluster and the horn fit into the open spot just perfectly.
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Horn in place, top view|
I added a small piece of inner-tube at the bottom where the horn touches the headlight and at the top where it touches the back of the instrument cluster. I replaced the Bracket and tightened it down and it held the horn very securely in place. For added security, I added the black plastic tie-wrap you can see in the photos. To ensure that the horn air intake wouldn’t suck up any dirt or water that might splash up under the windshield; I added about an 8” length of tubing and secured it in place with a tie-wrap. I replaced the windshield and the whole installation pretty much disappeared.
I’m a gadget freak and an electrical nerd. I want to accommodate stuff like GPS, heated clothing, HID lighting, auxiliary lighting, satellite radio, alarm, etc. but I need to have the electrical installation to be neat, professional, reliable and easy to service. For that reason, when I bought the horn, I also bought the “Electrical Connection Power Distribution Plate” (Twisted Throttle p/n: EC.02202), and the “Electrical Connection Master Ground Block” (p/n: EC.02207). The Power Distribution Plate gives you a central point to hook up all your electrical accessories, with 6 individual fuses and a 30-Amp master fuse. With the Master Ground Block, you get a central point for good secure grounds, connected directly to the battery, with 8 individual screw terminals, each of which can be stacked, if necessary.
Again, the problem was where to mount these rather bulky components in a place that is easily accessible for service? Then I realized that we K1200R owners have lucked out! The reason we have to make do with 4 horse-power less than K1200S owners (gee, only 163hp - - what a drag!), is that the K1200S has two air intake manifolds while the R (and R Sport) has only one. On the left side of the bike, under the tank cover, there is an empty space and the mounting bracket where the manifold would go on the K1200S.
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Electrical Panel, top view|
I fabricated a 1/8” aluminum plate to slide into the mounting slots where the intake manifold would go. It is held in place by two plastic “Latch Strikers”, BMW p/n: 13717672549 (see photo). On this plate, I mounted: the Power Distribution Plate and its relay; the Master Ground Block; and the Stebel Horn Relay. The Latch Strikers hold the plate securely in place, but it can be very easily slid out for service.
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Clip securing electrical panel|
I followed the instructions and connected the Power Distribution Plate and the Master Ground Block to the positive and negative terminals of the battery. I connected the power lead for the horn to the Power Distribution Plate. To the Master Ground Block, I connected the grounds for the two relays and the horn.
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Electrical Panel, side view|
The Power Distribution Plate has a relay which is wired such that the plate receives power only when the ignition switch is ON. I picked up this signal by patching into the positive lead of the BMW accessory socket on the left side of the bike, below the seat. Finally, to activate the horn relay, I patched into the positive lead from the stock horn switch, right at the stock horn. The stock horn still works, but you’d never know it because the Stebel Nautilus completely overpowers it.
When patching into these stock BMW wires, it’s best to use solder, if you know what you’re doing. If not, you can use wire patch connectors. Whichever method you use, make sure the connections are very secure and that there is NO TENSION on the wires or connections. Be sure to insulate the connections with quality electrical tape or heat-shrinkable insulators. For all your wiring, be sure to use good quality wire of the appropriate gauge. Remember, that this horn has a 30-amp fuse! Rout the wires carefully to avoid chaffing and secure them with tie-wraps to keep them in place. Make SURE there is no tension on the connectors. Also, as your grade two teacher said when you were learning to print, “Neatness counts!”
When routing your wiring to the location of the mounting plate, remember to leave enough slack to allow the plate to be pulled out fully for service and fuse replacement. As you can see from the photos, I failed to do this and I have to disconnect one wire from the Ground Block in order to pull the plate out far enough. Doh!!
|Installing a Stebel Nautilus Air Horn on a BMW K1200R: Electrical Panel, pulled out for detail|
That’s about it. Good luck and ride safely. You’ll have fun watching that poser damn near choke on his cell phone as you blast him with the Stebel horn when he wanders into you lane.
This post was posted in Stebel Nautilus 12-Volt Air Horn