Its beautiful country. I highly recommend packing a bit of fishing gear as the trout fishing along the trail is excellent. Also try to avoid the bike rally season (late July-Early August) as the Hills are very crowded. Thousands of ATV riders pack the Forest Service roads during the summer as well.
There are companies that will haul your bikes back to you if you choose to just do a downhill segment. I highly recommend early October as the time to go. The Hill City Super 8 is my preferred hotel. Good luck.