If you want real singletrack - you better get to Gallup, NM's Adventure Capital. The High Desert Trail system, named after the late Charles High, is a stacked loop system with narrow, single track trails with great vistas and cap rocks. The three loops are named First Mesa, Second Mesa, and Third Mesa, and go from easy begineer to intermediate to technical, respectively. Two trailheads at both ends make this very accessible from either end of Gallup.
Great for an afternoon loop mountain bike ride with the family or all day epic ride. This is a mountain bike specific designed trail system that is very well marked and has parking and substantial kiosk at both ends. Map/signs are posted at all intersections.
The High Desert Trail System is home to annual events such as 'Dawn Til Dusk', a 12-hour endurance mountain biking race; the High Desert Screamer, a series of mountain biking races; and the Squash Blossom Classic, running and biking events.
This system was designated as an National Recreation Trail in 2012 by DOI Secretary Ken Salazar. More information: http://www.americantrails.org/NRTDatabase/trailDetail.php?recordID=3778