Originally Posted by Lion BR
You may do this on another time, but I looked at your map and noticed your northern loop does not go to Glaciar National Park, in Montana, but goes close enough. I have not been there, but some people from that area have suggested one day I ride that area and they especially mentioned the Going-to-the-Sun Rd.
At the northern apex of this trip they'll still be quite a bit south of Glacier and Going to the Sun Road. It's an awesome ride but not something I'd recommend doing in a one-day loop, it's best savored at a slower pace. Glacier is gorgeous, but I actually preferred my experience on the Canadian side of the border (Waterton - Glacier Int'l Peace Park), less traffic, better camping, fewer folks on the hiking trails. It's all glorious, though, best to see it all!
My son and I did all that several years ago on a 3-week ride up the Canadian Rockies. If you've never ridden the Icefields Parkway, you must do it before you die. Simply amazing.
I need to win the lottery, quit my job, and just take my lovely wife and go riding. So much to see, so little time.