XTERRA Snow Valley, Part I:

Had fun pre-riding.  Kids rode too, as far as they could given the steep and sandy trails.  No, that's not a preemptive excuse, but the MTB is definitely a growth area for me:

One of the benefits of pre-riding, is, of course, working out the kinks.  One major kink I found turned out to be a residual Tucson thorn that flatted my tire. 

When I use a CO2 cartridge to fix a road bike flat, I pre-inflate to 20 or so PSI with the hand pump and check the tire fit before topping it off with the cartridge.  This leaves the new tire right around 100 PSI.  I attempted the same strategy with a MTB green slime tube and a 25 gram CO2 cartridge.  Apparently, this pushed the pressure too high.  Results were less than sublime.  Feel free to add your own caption.  We did: