Yep, sorry. The closest thing we had was the slalom course and north shore style trails at Challenge Park Xtreme in Joliet, but they stopped the biking thing a few years ago. Nowadays, you have to go north to Marquette, Michigan, or Snowshoe, West Virginia. There's some fun singletrack to be found off the Des Plaines River Trail and in Palos Heights. Kettle Moraine is ok, but too "Disney" for my tastes.