Originally Posted by raybo

There are two ACA routes accessible from Portland: the Lewis and Clark trail, which goes up the Columbia Gorge, and the Transamerica Trail, which goes close to Bend.

The Transamerica Trail heads east from Eugene. You can take the Willamette Valley Scenic Bikeway from Newburg down to Eugene and then catch the Transamerica Trail to Sisters/Bend. I've ridden from Newburg to Sisters on this route and can recommend it. You do have to climb over Santiam Pass (you can also try the shorter/steeper Mackenzie Pass, if it is open), which requires some well-shouldered freeway riding but the ride up from Eugene is fabulous. Here is my journal of that ride (see days 1 to 6).

Have a great time.