The following is my experience and is based on being self supported. If they will be sagged it will help some. Will your riders be carrying their gear? Will they have to do their own cooking and shopping?
It wouldn't be a reasonable pace for me, especially self supported. That is 95.5 miles per day. Certainly possible, but do you really want to ride pretty much a century a day? I don't and I doubt that many do. It would seem to prevent spending any time seeing the country as you go. side hikes, time off to go rafting, rest days; any of that kind of stuff would seem to be minimized or completely eliminated.
We met some folks who thought they would maintain a pace like that on the TA, they fairly quickly decided that it wasn't reasonable. They were self supported, but I think they would have come to the same conclusion if they weren't.
We did the TA (a similar distance) in 73 days and didn't feel like we were loafing. We did start a bit slow and trained as we rode, but still I think that our mileage was reasonable.
If the NT is similar in difficulty to the TA...
I would see 8 weeks (56 days) as pushing very hard and 12 weeks (84 days) as taking it somewhat easy. Longer isn't out of the question though.
Bottom line why make it a grueling ordeal? It should be fun; it won't be for the average rider if done in 45 days.
This message was edited by staehpj1 on 1-28-08 @ 8:51 AM