What locals once called the "Secret Trails" isn't so secret anymore. The USFS has adopted many of them into what is now called "Soldier Wash Trails." You may not see them yet on the local maps -- they are newly adopted - but the signage on the ground at trail junctions is great (see photos). Some of the original "secret trails" are blocked off, but what is there should be considered a must ride when in Sedona. These were originally renegade trails developed by local mountain bikers. They flow like a good mountain bike trail should. The accompanying TOPO map describes an 11-mile loop that includes the Soldier Pass Trail with the Soldier Wash trails.
There are several ways to get into the Soldier Wash Trails network. The attached TOPO map starts at the Adobe Jack trail head. This is located along Hwy 89A about a mile west of the "Wye" junction with Hwy 179 in Sedona.
http://www.singletracks.com/item.php?c=1&i=5867