Here is a cool post on the best mountain bike trail in Phoenix, Scottsdale or Fountain Hills.
DIFFICULTY: Easy with a few tricky spots
Just when I thought mountain biking in Scottsdale and Fountain Hills could not get any better, we discovered this great trail head that connects to Pemberton Bike trail system. From Scottsdale, take Shea out to Fountain Hills and then head north on Palisades Road for about four or five miles until you see the signs for the Sonoran Trail Head. Follow the road from the parking lot through the guard gate and pass a few incredible homes and LUXRY FOUNTAIN HILLS REAL ESTATE.
This trail head is a hidden gem for mountain bikers. The facilities are probably the nicest of any trail head I have ever been to, and hardly anyone knows about it. The parking lot is usually half empty. From the trail head, just follow the signs for about a half mile to the entrance to Mcdowell Mountain Regional Park system. Pay your $2 to help keep the trails open to all and maintain them and then head back into the trail and connect to Dixie Mine. This trail is less traveled than the other main trails in the Pemberton Park, and you can connect to the rest of Pemberton with some killer views and a few great climbs and descents. Follow Dixie Mine for a couple miles and then you will see the actual Dixie Mine. Pretty cool little detour if time permits, but then connect back from Dixie Mine to Pemberton. Today we took Pemberton West back into Coach Whip and then Coach Whip back to Dixie Mine. Take a right at the Pemberton junction to add anywhere from another 8 to 12 miles of awesome fast single track.
Check out the whole article here: http://topbiketrails.com/top-mountain-bike-trail-in-fountain-hills/