UM Pass Professional Review and Guide
"This 18-mile ride is almost a straightaway loop, except for the short, one-half-mile spur at the beginning and end. With 2,000 feet of climbing involved, including a physically challenging 2.5-mile climb to UM Pass, the ride is rated moderately difficult; ditto in regard to technicality, owing to a diversity of riding surfaces that include pavement, graded two-wheel-drive road, dirt double-track, eroded and mucked-out ATV trail, and, most notably, a very fun and quite hazardous descent from the pass that serves up a series of huge humps built to control erosion and/or to preclude large motorized vehicles from accessing the old jeep trail.
Lower your saddle before diving off the pass and maintain a light touch on the brakes, particularly the front ones, or you’ll chance going ass over over teacups in a big and painful way. Also before descending, take a good look around from UM Pass, which is basically a saddle sitting 1,000 feet below 11,610-foot Mount Marvine to the south and, to the north, 11,537-foot Mount Terrill. General location: 50 miles southeast of Richfield."