I bought the PIAA Sports Horn kit ($38 on Amazon.com) in the 500/600 hz version. The box it came in promised "high pitch European sports car quality". Not sure if that's a good strategy though; now when I hit the horn, cagers will be looking around for a Ferrari or Lamborghini.
The kit is pretty simple. In addition to some generic instructions, you get the 2 horns and 2 ground wires as shown in the photo below.
This kit is basically plug and play in the sense that the spade connectors from the stock horn fit the PIAA horns and then you just bolt them on. According to the manufacturer, the horns only draw about 4 amps each so there's no need to use new harnesses and relays etc.
That's not to say there isn't some fiddling around though. With my big hands and lack of X-Ray vison, I couldn't get behind the stock horn bracket to hold the nut with a vise-grip and there's precious little room to work in that space anyway. So I took off the lower cowling and inner fender panel on each side. That can be a PITA but if you've done it before, it's only about a 20 minute job. With that done I had the access I needed. The stock horns come off easily; just get a vise-grip on the nut around the back, grab the horn with your hand and turn CCW.
I chose to mount the PIAA horns in the same place as the stock horns and that brings up another minor annoyance to deal with; because the ground terminal on the PIAAs is lower down on the horn, the FJR's ground wires are not quite long enough to reach. You can come up with your own work-around (e.g. a splice) but I was able to make it work by teasing some slack out of the ground wires by pulling them out of their harnesses a bit. I also filed a notch in the inner fender panel on the RHS to get some more slack.
You could get around the too-short ground wires by mounting the PIAAs higher up on the bracket. See photo below showing the alternate mounting position at the allen head bolt. If you decide to mount there, don't forget to move the rubber washers up. Apparently they are important for vibration damping.
The following photo shows how the horns look from the front at fender level:
The next photo shows the side view also from fender level. Actually, the horns aren't noticible from the side and you only see them here because of the paper background.
Finally, thanks to my tool monkey and shop foreman for helping out (not). I think he was after my beer!
The horns sound really good and just as advertised. They're much louder than the stock horns without the Roadrunner "meep, meep" quality. Come to think of it, kinda' like a Lamborghini.....
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