I remember taking my Goldwing up to the top of Petit Jean State Park. I think the incline was 18 degrees if I remember right plus tight switchbacks. That was with a injured bike after hitting a small deer or dog at dusk. Couldn't really see enough to tell.
Three good landscape shots. I like the way that your cropped all three of these photos cutting out the blue sky on the third and showing the beautiful sky on the first two.