If I were planning a day ride loop from Gorham, I'd think about maybe something like this:
Start uout east on Rte 2 then head down Rte 113 through
Evans' Notch to
Hurricane Mountain road, then up 302 to Bartlett to run down
Bear Notch Rd. From Passaconoway west across
the Kank all the way to Vermont. Ride up through
Groton State Forest on Rte 232, then head back east on wide open Rte 2. Take a short back road bypass of St Johnsbury and Rte 5 south to Barnet, cross back into NH and some back roads up to Littleton, hook up with Rte 3 to Twin Mountain, then rte 302 down through
Crawford Notch. When you get back to Bartlett, you'd have to ride
Bear Notch road again (darn!) and then ride the last bit of the Kank you missed in the morning. Just before Conway, get onto West Side road and take that up to the top of
Cathedral Ledge for a nice lookie loo. After the photos ride up through
Pinkham Notch past Mt Washington and back to Gorham.
That's be 285 miles and ~ 7 hours of quality saddle time.
(Click below image for full screen, interactive map in a new window)
(I have a GPS file of the above route if you think you might want to run this)