This is very good singletrack that is 90% swoopy, downhill fun (little short uphills). There are many changes in the forest from open wildflower slopes to old growth forest. The Tire Mtn. section is great singeltrack with a bridge crossings and tight switchbacks. Cloverpatch is a bit underridden (bushes and flowers growing over in areas), but easy to follow. Another option instead of Cloverpatch is to continue on to Winberry Divide to Eugene to Crest, but this would be a shuttle ride (well worth it!).
Whether you shuttle(100% singletrack) or ride a loop (70% singletrack), follow directions for Alpine Trail to Windy Pass (see earlier post). The start of Tire Mountain is approx. 1.6 miles down the Alpine trail from Windy Pass (rt. at log sign), 6 miles down takes you to Cloverpatch (left), 5 miles down takes you out to FS Rd. 5826 (rt) 3 miles downhill to FS RD. 5821(lft./North Shore Rd) 6 miles back to Westfir. Stop by Willamette Mountain Mercantile in Oakridge, buy a map, and they can easily show you the directions.
http://www.singletracks.com/item.php?c=1&i=3333