Phoenix has an overwhelming amount of biking trails and you need to go out there and ride them, but first a few notes:

1. The first rule of mountain biking in Phoenix is: There are no easy trails.* The heat here in Phoenix seems to do something to our heads: moderate trails seem easy, hard trails seem moderate, and stupidly impossible to ride trails seem merely hard. Take Desert Classic as an example, locals call that an easy trail. It’s not. Oh sure, there are some flowing flatish easy bits on it, but those easy bits are flanked by short nasty, technical, and craggy ascents and descents. It’s also kind of long. No, 17.2 miles (out and back) may not seem all that long, especially since it skirts the bottom of the mountain, but when it’s 110 F in the shade (there is no shade) that can be the longest 17.2 miles you ever ride.
2. I’m not a great rider, but I do OK. When I say a trail is hard, a lot of you may find it rather easy, or vice versa.
3. Not all trails are cut out for mountain biking. Some, like the beginning of trail 304 are just too nasty to ride up. Others, like the Squaw Peak Summit Trail are flooded with hikers.
4. Hikers have the right of way. Don’t be a jerk. If you don’t at least have a bell on your bike, you shouldn’t be riding trails with hikers.
5. It’s a dry heat here in Phoenix so you won’t melt, you’ll just burst into flame.

* Except fro Papago Park, that’s a pretty easy trail.