imported post
First of all, it is the speedometer, not the odometer. But don't blame Jimmy Carter for that one. That was Joan Claybrook's doing. She was the enemy of motor vehicle enthusiasts of all kinds.
I notice you have one of those fancy units with downloadable maps. I have a simple yellow Garmin eTrex, which I had mounted on the 7/8" diameter handlebars of my dual sport (great for finding your way out of whatever you rode into, or refinding your way back to a great camping spot, etc.) When the speedometer quit on my 1200LTD, I hacked off the stem of an old 10mm mirror, welded a piece of 7/8" steel tubing to it, screwed it into the unused mirror mount on the clutch master cylinder, and attached the GPS unit to it. I found a RAM mount specifically designed for a 10mm mirror mount and ordered it. I will use it mainly for a speedometer/odometer. I have another GPS, a Garmin eTrex Venture, that fits the same cradle. I'm a bit old fashioned, and still like maps, especially on the highway. If I get lost in town, I will pull over and look at a map, figure out how to get where I'm going, then get back on the road. I don't like looking at a map or pushing buttons while riding, especially in town.