I was just damn lucky. Fortunate. Blessed even. With everything looking ok, I took the Dakar out for a ride to the Norton Gathering (see season opener). It is about a 60 mile roundtrip, and the day was a beauty if a little chilly in the morning. I had cleaned out the float bowls and synced the carbs and it seemed to be running very well. On the way back I noticed a vibration between 60 and 65 MPH. It went away above or below, and I suspected that I lost some weights and the rear wheel needed balancing. I rode the remaining 10 miles home staying below 60 MPH (you have no idea how hard this is on beautiful back roads).
Once I got home, I decided to check out the rear end, and noticed a slight delay between turning the wheel and the tranny engaging. Hhhmmm. Then I gave it the spin test known to owners of the R100GS, and heard the sound that you don't want to hear. When the wheel was spun in reverse, there was a distinct clicking sound. The good news is that this usually means that your gearbox is ok. The bad news is that it means you have a bad u-joint. I pulled the rear apart and once I had it out of the swingarm, the forward u-joint was indeed shot. Not just shot, but probably a few miles from coming apart and doing major damage to the swingarm, before locking up the rear wheel !!
All this when everything felt fine 70 miles before. I had done the spin test at the seller's house, and again when I got home. Like I said, blessed. Now it is off to spend the money I thought I scored negotiating this deal, on a new driveshaft.