Have done it on a quad a few years ago. It was an awesome experience and the routes are worked out to include a bit of all types. You can easily do 150 - 200km a day, even if very unfit. There are short technical stretches, but mostly dirt roads and so on. When we did it, at least two kids at around 6 or 7 (one of a quad and one on a tweelie) managed and three or so guys on DS type bikes.
- Have back up. If not your own buddies, arrange with organizer to use their truck. They can then transport your camping stuff, etc. leaving your bike reasonably free of baggage during the daily rides.
- Watch out for dust. If the trip is before the start of the summer rains, dust will be a nightmare.
- Enjoy the ride. It is awesome and there is no rush. You have roughly 10 hours a day to cover the distance.