Ok, here's the mount hardware I use on the 2620. Should be good for the 26XX and 27XX series Garmin units. Looked at several before getting these pieces and talked to an engineer and a tech at both RAM mount and Garmin. Both were comfortable that the fancier (and considerably more expensive) rubber isolated mount system often recommended for the hard drive based Garmin units was unnecessary for a rubber mounted bike. For a snow mobile or a rigid, yes. For our bikes not a big deal. Several long trips with anything from 12 hour days with the GPS unit continuously running or trips over really rough roads have proved it to be an safe mount system (at least so far). I've also got some software that I can use to check the hard drive in the Garmin unit for surface errors. Have plugged it in to my computer and checked it a couple of times. After a fair bit of weather and rough road abuse it still reports 100% error free. So the mount in conjunction with our rubber mounted engines really seems to work ok.
There is also a clamshell type cradle unit to attach to the GPS unit itself that is far more common than the one selected below. The GPS unit just snaps inside of it and it's like $10 cheaper. I watched a 2610 come loose from one of those in a bass boat once. So for a few bucks more this one actually locks down on the GPS unit and has a locking screw you tighten up to make sure the lock stays locked. It also comes with a little keyring torx tool to carry with you to release the screw should you ever need to. Seemed well worth the small difference and it works great in practice.
The following two links from GPS city show everything one might need for a simple, easy and effective motorcycle installation. With these parts you've got u-bolts for either standard OD handlebars or larger ones like the Wild1 bars. The only thing I did to alter the stock pieces at all is put a couple of thicknesses of heat shrink tube on the u-bolt to avoid any metal to metal contact anywhere against the handlebar. I only put the u-bolt mount on the bike when I'm going on a trip that I'll use the GPS for. Rest of time I take the U-bolt based mount off (2 minutes with a 7/16" deep socket). After several on and offs and lots of hours on the handlebar there's not a mark on the bar.
http://www.gpscity.com/item-garmin-streetpilot-26xx-motorcycle-cradle-and-cable/sp26cradlepow.htmhttp://www.gpscity.com/shipswith-npi-large-steel-rail-base-with-round-plate/ramb101-231l.htmThe first link up there includes the motorcycle cradle and a power cord that you could use either for a hard wired install or a removeable install. I personally don't use the audio component of the cable; but it's there if you want it. I cut it to length to reach from the GPS unit to the cig lighter plug and put a connector on it for the lighter plug. So the whole thing (minus the u-bolt mount) comes on or off the bike in 90 seconds without any wires draping in front of you or permanently tied to bars coming from a hardwired mount inside the fairing.
A really good and easy to use plug end if you choose to do it this way comes from radio shack. It's fused right in the plug housing itself. The fuse is easily serviceable. It's got a boot to make it good in wet weather. It's got a little pilot light so you know if the connection is good or the fuse has blown. And it connects to the wires you'll take to it with spring loaded clamps so it is super easy to make the connection (but it still holds tight and works great). That they are cheap is just icing on the cake.
I use this plug for any cord I make up to go to a lighter connection or anytime one needs replaced. Radio Shack's links don't always stay static. If the link is busted later the part number at Radio Shack is 270-1509.
http://www.radioshack.com/product/index.jsp?productId=2062263&cp