Time to customize!
The Howard's Dynamic Duo comes with it's own bracket that replaces the stock horn bracket. Then what you're supposed to do is mount the air compressor in the stock cowbell which in turn mounts to this bracket. The trumpets also mount to this bracket as well. All in all, it's a pretty good design, that is, if your motor is hard-mounted. If you have a rubber-mounted motor, the whole bracket assembly including the horn and compressor tend to rock with the motor, and I just didn't like that. Plus I've heard that this rocking and vibration places additional stress on the horn, resulting in cracks and breaks later.
My goal was to (1) hide the compressor, and (2) get the horn off the motor. All I needed was a frame clamp and a piece of bar stock. The frame clamp is just your ordinary frame clamp, nothing special about it. Although it is chrome, I’ll probably paint it this winter so that it blends in better with the frame. The bar stock I picked up at my local Home Depot for 5 or 6 dollars. It’s a piece about 14 inches in length, 1.5 inches wide, and 1/16” inch thick. All I did was bend it in sort of a ‘Z’ shape, mounting one end on the frame clamp and mounting the horn at the other end. I took frequent measurements and made numerous trial fits until I had the horns where I wanted them. After I had the bracket fabricated, I cleaned it up really well with some emery cloth and shot it with good ‘ol gloss black Rustoleum. Maybe one of these days, I’ll get it powder coated just for better durability but so far the paint has held up flawlessly. Finally, the mounting hardware is just ordinary stainless steel bolts and acorn nuts, again purchased at the local hardware store.
I didn’t want to clutter up the left side of the motor with the twin air horns AND the cowbell. Instead, I decided to make use of the empty compartment forward of the battery box on my 2003 Road King Classic. Having a bagger has its advantages!
In the battery compartment on the right side of the "forward bulkhead" (looking forward), you should see a single unused hole (I seem to recall it was a threaded hole but was not being used for anything). What I did was take my Dremel tool and enlarge the hole enough to accommodate the bolt needed to mount the compressor. If you look at the top of the compressor, you should notice a square slot sized to accommodate a 1/2" bolt head. What you do is first insert the bolt through the bulkhead with the head of the bolt in the forward cavity and start a nylon locking nut on the other end in the battery compartment. You then insert your compressor into the forward cavity and slip the head of the bolt into the square slot on the compressor. Hold the compressor in place and tighten up the nut in the battery compartment. Snug it up good but don't over-tighten. Also, this job goes a lot easier if you have everything else wired up and installed ready to go. This way, you just plug the positive/negative wires into the bottom of your compressor, slip it into the forward compartment, and then bolt it in place. In the picture below, you can just make out the compressor and the clear vinyl air tube going to it.
The end result is a nice clean installation.
