This route is about 10% pavement, 40% gravel, 40% big rocks, and 10% non-existent. There's a turn during the burned forest section in the first half that doesn't exist (you can see it cut the corner of the Sisters to Palisade segment, which is correct). Later, just after the turnaround back towards Sisters, the track disappears, and you can just barely pick it out. Would not recommend if you get scared bushwhacking, and certainly not after a good rain. I had to walk sections and it was totally dry. Would recommend MTB tires with low pressure, like I said lots of big rocks and most of the normal-sized gravel is very washboarded, often all the way across and thus unavoidable. For all the negatives I've said though, very pretty throughout and great views.