Ran the Jack Pine today, woods were tight and nasty, with lots of little stumps just where I wanted to put my tires
Finished the last timed section to find that my rear tire (TuBliss equipped) was flat, flat, flat. The good news was that the tire was still firmly on the rim, and at least I had something to blame my score on ... now to find the problem. No needles or thorns, no sidewall slices.
It turns out that the core of the valve stem on the main (tire) chamber had worked itself ever so slightly loose allowing the tire to go flat - nevertheless the tire was still on the rim and with a tighten of the core and some fresh air the tire assembly is as good as new (and certainly better than the guy with twenty zip tires holding his rear tire to the rim)