K1600GT - Part 4: Headset Extension Lead Installation
With the Autcom SPA-2 unit located in the tank bag I was not wild about a passenger headset cord running across my lap to the rear seat. This meant a 7-pin Autocom headset extension lead was going to have to be routed from the tank bag to the back of the motorcycle. Given the overall length of this bike I went with the 6.5 foot (2000 mm) extension lead (part #2136). It was just long enough to get the job done. If there were any more twists or turns in the routing it would not have reached the tank bag.
Before doing any routing my first step was to wrap the entire extension lead with black 1/4 inch UV resistant polyethylene spiral wrap. I ordered it from McMaster-Carr on a 10 foot spool (part # 7432K625) and used almost all of it. The routing process then started at the back of the bike with the tail light / indicator light module, luggage rack and all body panels removed.
Since the Powerlet socket added earlier was under the left side of the luggage rack I decided to mount the headset connector on the right side. Similar to the power socket, this would allow my wife to plug in below and slightly behind her right hip keeping the cord from her helmet away from her legs and knees.
A rubber socket holder (Autocom part #2425) was positioned so the connecting plug could be accessed with the side luggage mounted and also not interfere with tail light housing once it was put back on the bike. Here is a photo of the plug positioned on the black rear side panel. Note the spiral wrap on the cord. (photo #1)

With the rubber socket now positioned, the black back side panel was taken back off the bike and the extension lead was channeled down along the outside of the frame all the way to the battery. Zip ties were put on to loosely hold things in place. Don’t tighten the zip ties just yet.
With the long end of the extension lead down near the battery go back up to the end of the bike and take the panel that goes under the tail luggage rack and slip the extension lead connector through the rear most hole in the panel. Put the black rear side panel and this panel back on the bike loosely with a few bolts.
Now, starting at the rear of the bike, go along the frame pulling the extension lead taut. You’ll need every inch this extension lead has to offer as you get down to the end of the routing process.
This photo shows the extension lead routed through the panel that sits under the luggage rack. (photo #2)


At this point, take the luggage rack and put it in place as if you were going to re-mount it. Since the left post of the luggage rack and the extension lead will share the same hole in the panel, make sure nothing is pinched. If so, move the extension lead around until the luggage post and the cord no longer bind. Slip a bolt in the luggage rack post for good measure just to make sure everything lines up. If all is well, go back and tighten the zip ties along the frame.
This photo shows the extension lead in finished form with the luggage rack and tail light/indicator light components back in place. Easily accessible but also nice and neat and out of the way! (photo #3)


Now let’s move to the middle of the bike. The next photo shows the routing of the extension lead over the rear frame where there is normally a gap between the passenger seat and the frame, then under the metal cross bar, and along the wires running from the Alpine audio unit. The lead then disappearing under the plastic mount that holds the tools and front seat. (photo #4)


The extension lead was then routed up along the center of the bike right under the left side of the gray plastic center body panel. Towards the top of the gas tank there is a channel to the left of the center panel the extension lead can sit in and run along. The next photo shows you what this looks like. (photo #5)


When you put the various body panels back over both the gas tank and air ducts make sure the extension lead doesn’t get pinched and actually stays in the channel and exits left of the steering column. This will ensure the extension lead will stay in place as the panels are tightened down and is well away from the steering head and handle bars.
The next photo shows where the extension lead exits from under the body work. It also shows where the second rubber socket holder is positioned, how the Autocom SPA-2 passenger headset lead coming out of the tank bag is routed, how the extension lead is flipped back to the rubber socket and then the two connectors joined. (photo #6)


When the passenger headset lead from the Autocom SPA-2 unit is not being used I just tuck it inside the left side pocket of the tank bag. The connector on the extension lead is then tucked inside the socket holder to keep it from moving around. You can see this in the next photo. (photo #7)


So there you have it. A convenient place on the back of the bike for the passenger to plug in their headset, plus easy access to the other end of the extension lead right at the tank bag!
Up next ... tapping the speaker wires for integration with the BMW Audio Sound System.
Dave











