On my BMW R1200RT I glued a RAM ball into the top edge of the inner fairing trim, to give me a mount for an old Nuvi 360 that I had. I wired a power socket to the battery under the seat and then routed a power cord up under the fuel tank and into the fairing, so it came out at the ball mount. It worked good until one day it rained. The GPS still works but is too dark to see even at full brightness. So off to ebay to shop a replacement. I scoured a fully functional used Nuvi 750 with updated maps for under $20 with the mount clip. It connects to the same power cord as the Nuvi 360. I put clear Gorilla tape over the speaker holes at the back and over the slot for the memory card (it came with a 4gig card in it). Then I applied painters tape on the screen, leaving maybe a 1/16" gap to the outer frame. Next I applied 100% Silicone caulk around the screen edge, and forced the caulk under the screen frame with a small piece of plastic. Pulled off the tape and smoothed the caulk with my finger. Once cured it will seal the GPS from rain. I found a video on youtube of a rider who did the same on his car style GPS and has worked in the rain for many years. Finally, I added a sun shroud I bought on ebay. So now I am set for GPS on my BMW for less than $50. With a bit more shopping I could have bought a used GPS with lifetime maps updates.