This is hands-down my favorite bike tour in the Pacific Northwest. The highlights are many (hot springs, secret caves, Alvord desert, milkshakes, historic hotels, Malheur Wildlife Refuge, etc.) and the remote nature of route makes for a bit more adventure than most tours in Oregon.
In traditional VeloDirt style, the route mixes gravel and pavement and is best suited for wider tires – I’d suggest 37c tires and up. My Salsa Fargo was perfect; however, a more classic touring setup would work just fine. Advance planning is critical. Water access, camping, weather, and road conditions vary considerably throughout the year.
I used to have a very detailed write up for this route. However, the route is now part of Ellee’s fantastic Cycling Sojourner guidebook. My suggested deviations from the book include: (1) enlarging the loop to add the Crystal Crane Hot Springs, (2) riding the “Patrol Road” through the refuge; and (3) riding the Steens Mountain loop road to the summit if you can (it’s only open a few months of the year).