One of the first critical modifications to my new Street Glide was to provide for listening to either the (built-in) radio of the Glide or the GPS that I mounted onto the dash. I learned very quickly that serious touring on a motorcycle requires a good GPS system. The built-in GPS systems are great, but also greatly over-priced. I originally used a Garmin but my latest is a Tom Tom. Both have their pros and cons, but neither has a screen that is visible in bright sunlight from the seat of a bike so being able to hear the voice instructions is critical, especially if you are wearing a full-face helmet! To that end I modified the Garmin, and now the Tom Tom with an audio out plug… the older Garmin with plenty of room in the case was easy, the Tom Tom, with its super thin case, was a bit more daunting.
This project included the following modifications to the dash of the Glide:
Addition of water-proof, marine quality, 12-Volt receptacle,
Addition of audio out jack, marine quality, 3.5 mm stereo,
Addition of base mount for GPS device,
Addition of separate switches for the left and right speakers of the built-in audio system.
Another item, not mounted, was a ‘black’ box that provides two audio in plugs and one audio out plug (to earbuds) with a toggle to switch between the audio in devices. This device allows switching between the GPS and the Radio while riding, and is temporarily attached to the top of the tank bag during a trip.
The picture below shows the location of the various dash mounted items on the bike:
The positions of the several items must be chosen carefully based on the layout of the wiring and components behind the dash. Clearance based on the contours of the front fairing is also a critical consideration. Note that both the audio out jack and the 12-Volt power supply jack are BOTH water-proof! (Marine Grade) The text, barely legible, to the left of the switch (dot on top) reads ‘Left Speaker Sw’, turns off the left speaker so that I do not disturb other drivers / riders, particularly at stop signs and stop lights. Just a miniscule consideration of their rights NOT to hear my radio. The 12-Volt jack uses the wiring from the cigarette lighter, not visible in the photo, but about 12 inches below. There was enough slack in that wiring with blade sizes that made the hookup a snap.
After locating the center-point of each item a pilot hole should be drilled, carefully, through the dash. I used brand new, sharp, Irwin Speedbor paddle drill bits with the tang on each side to drill the holes for everything except the GPS mounting bracket. Using the pilot hole as a guide, slowly apply pressure on the bit until the tangs on the bit create a single circle in the plastic of the dash. DO NOT DRILL THROUGH BEFORE using the pilot hole to create the same ‘circle’ on the inside of the dash. This procedure will create a clean hole, when drilling is alternated from the front and back of the dash applying just enough pressure for the paddle to cut away the plastic until a ‘washer’ like plug is free from the dash.
I tried out these modifications on a long tour yesterday and they all worked great. Being able to hear clearly the voice instructions of the GPS while giving your full attention to traffic is without a doubt the most important element of these modifications. Unfortunately, the manufacturers of GPS systems seem not to realize that motorcycle riders absolutely need an audio out jack on their GPS systems so adding a jack, while difficult is an absolute necessity for any serious tourer.