I wanted a mount for my Garmin Quest that is difficult to remove, and protects the GPS unit itself, especially the screen. I couldn't see spending over $100 for the wired RAM mount, which wasn't very protective and didn't offer any resistance to theft. The Touratech mount was great but even more expensive. Lacking any other options I made one:
I built the first prototype using 26 gauge sheet metal as a base, and aluminum angle stock cut to frame an acrylic window over the GPS screen. The GPS is held in place by 1'' nylon standoffs covering #8 screws. I used bits of rubber from a dead tire and some leftover pipe insulation for padding.
I had to wire in a 7805 fixed voltage regulator to convert 12v to 5v:
The hardest part was figuring a way to make continuous electrical contact with the input pins on the back of the unit. I ended up looping wires through a piece of acrylic, precisely aligned with the back of the unit. Next I need to connect to the audio output pins and wire up an amplifier for a helmet speaker.
I bent a piece of metal I had lying around to attach the whole thing to a rope clamp that fits nicely on the KLR650's cross bar.
All the materials came from Home Depot except for the electronics/wiring and the brass nuts on top. The top frame used to be held on with wing nuts but I got these really cool looking knurled brass nuts from Lowe's home center. Totally unneccessary but they give it a 19th century scientific equipment look. How could I not get them?
Overall it worked better than expected for a prototype. I'd like the next version to be mounted inside small plastic box to further protect the GPS unit and clean up the looks, but as long as this keeps working it may be a while before I get around to it.