I have a Valentine V1 that I run on my touring bike (Honda ST1100). Use an earphone for the sound and mounted it kinda high behind the windscreen so it's almost a HUD type location.
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Milled a hunk of Delrin out for the mount. Have sused it for the past 5 years and the mount still works like a champ. Easy to get the V1 in and out as well. Mabe not the prettiest thing in the World, but it works very well.
Weather protection: I keep a baggy in my side fairing pocket. In rain, I just throw it over the V1 and hold it on with a small bungee cord. Doesn't get much direct rain as it's behind the windshield.
If you need help making a mount, just email me and I'll help you out with the machining if you need it.
Eric
EaracheMS@Gmail.com