I don’t post to the forums much but as you are talking about coming to play in my back yard I thought I would offer some personal insight. First highway 53. This is a short ride about 18 miles from Wheeler up to hwy 26. Most will ride one way turnaround and ride back. It is well worth it. This road offers tight turns and some sweepers. It is in very good shape and lightly patrolled by law enforcement. April and May can find gravel on the road surface, this is usually clear by June. There is some gravel drives and access roads that may spread debris onto the hwy surface. This is the only drawback. I would rate this gem of a road at 9 out of 10.
Another good ride is Hwy 47 starting at US 26 north to the town of Vernonia, on to the little burg of Mist and out of the coast range to the town of Clatskanie. The road up to mist is in great shape but you need to be on the look out for deer in the morning and evening. From Mist to Clatskanie the road is used by a lot of log trucks and is very narrow at points. This stretch has a lot of tight low speed turns. If done on a Saturday or Sunday and ridden with a bit of caution it is a absolute blast. The one note is that at Mist you need to take a right turn to stay on hwy. 47, otherwise you find yourself on Hwy. 202 on the way to Astoria. A short word about 202. Last year it featured pot holes that would swallow a Cadillac. It also has sections that had rocks which had fallen from the hillside onto the roadway, and cracks 10 to 15 feet in length 3 to 5 inch wide and as much as 5 inch deep. I know of three riders that have gone down on this road, still if you use a bit of caution it is a great ride ending at Astoria.
The Three Capes scenic route west and south of Tillamook is a good ride, although by June you may find a lot of tourist. These roads are in good shape but not all the corners are well marked. A few years ago a friend missed a 90 degree turn and lunched his Suzuki and himself into Tillamook bay. Still on a sunny day you can’t beat a ride on the Oregon coast.
I hope some of this information helps. As I said living in Portland makes the north coast area like my back yard. All of the roads can be done as a day trip from Portland and there is a lot of great places to see.