You could go to Moab and stop in Fruita Colorado for a day or two. It'll be toasty but not that bad. Crusty Butt riding is great and the views are even better, but the best riding in Colorado IMHO is in Durango. You get everything from desert riding to mountain forest trails and lots of it.
Check out this link.
http://www.durangocoloradousa.com/co...ainbiking.html
A great loop would be a stop in Fruita first, then Moab, followed by Durango and then finshing up in Crested Butte. Now THAT would be a trip to remember.
Fruita is only about 4.5 hours from Denver, another hour drive to Moab, then about 4 hours drive to Durango and about 3 hours from Durango to Crested Butte.