Not 5 minutes after being soaked in the rain, and 10 minutes from first camp, Danny starts yelling in my ear (helmet comm system),
"YOUR REAR TIRE IS SPARKING! YOU HAVE A FLAT OR SOMETHING, PULL OVER IMMEDIATELY!"
Luckily there was a rest stop off-ramp only 200 ft away. We pulled off and slowed down, CAREFULLY, and he says it's still sparking. I'm trying to figure out how I've been comfortably cruising at 70 on a tire so flat that the rim is sparking. AND trying to figure out how I am going to get past a flat rear tire to continue the adventure.
Well we stopped, and it turned out my tool tube was half-hanging off the front of my bike. It had a metal pipe clamp holding one side, and plastic zip ties holding the other. And what broke? The metal clamp. It had been dragging long enough without either of us noticing that it rubbed straight trough the tube, and the asphalt was lightly grinding one of my wrenches. Hence, the sparks.
Strapped it on the back. Hit the road gain.