Big Bend Ranch State Park offers some of the greatest mountain biking experiences anywhere. The latest issue of the park's newsletter El Solitario has lots and lots of information about mountain biking in the park, including descriptions of many of the park's trails. You can download a copy here.
Because of the tough desert climate and terrain, riders are cautioned to bring the equivalent of two large camelbacks and always carry two spares....prepare for some wild fun!
For information about cycling throughout the Texas Mountain Trail region of Far West Texas, visit: www.texasmountaintrail.com/bike