This is just one of many probable cool loops that can be made in this area. We did this in the fall of 2006 as a "post-season Tuesday night ride", and had a great time.
Since there are a lot of intersections along the way, and we don't remember where they all are, we'll make a vague (but pretty safe) description of this ride.
Begin at the parking lot at the crest of the Steese on Cleary Summit. Ride up the wide dirt road about 0.8 miles, just past the group of buildings. Turn left onto Fairbanks Creek road, and stay on this for about 2.5 miles, turning left onto the trail head of the Fairbanks/Circle Trail. This comes up quickly on a descent, so be on the lookout for a wide area in the road. It's marked with a sign as well.
Follow this "trail", looking for signs at major intersections. Other than that, stay on the main trail. There are some marvellous vistas to enjoy, so leave time in your ride for some gawking. You'll be going through the 2004 burn area, so parts of it are quite stark.
After, what, seven or eight miles, you arrive at a major intersection at the bottom of a fast, rock strewn descent. The Fairbanks/Circle trail continues straight, but we turned right to make the loop shown. There's some fine, fast descent, but you have to pay for it.
You end up back on Fairbanks Creek Road, about five miles from where you turned off of it, with a good grind ahead of you to pay for all that descending. S'ok though. The uphill isn't all that tough.
Figure 2 - 3.5 hours to complete the ride. Lotsa energy output, so bring eats.