My husband used to drive a truck between Sisters and Salem on hwy20/22. He is also a very experienced cyclist with many hundreds of thousands of miles in the saddle. When he saw that you were going to ride those roads, he frowned. The scenery is beautiful, but the motorists are some of the least civilized that OR has on offer. Choose your times of day with care; there are commuters along that stretch. If there is oncoming traffic at the same time as you are being overtaken, the overtaking motorist is going to be very reluctant to use their brake and will likely try to squeeze by. Much of the road from Santiam junction to the Detroit Ranger Station has little to no shoulder.

Oh well, the bad stuff isn't that many miles. Have a blast. With a bit of luck gasoline prices will rise and the traffic will be so light you'll be in cycling heaven.