Big very very careful, this can be an extremely dangerous trail. Also, watch out for erosion on the trail. I haven't ridden after it rains, but the trail looks susceptible to washing out. The climb from the bottom of the canyon back up to Deadwood is longer and higher, but not as steep in general. But there are a few short sections in this area that are the steepest on the trail.
Deadwood makes a good lunch break.
Deadwood road is a dirt road that gets some automobile traffic, so it is not technical. It is wide, and seems to be well maintained. Deadwood road is a steady climb, but it is not very steep. Be careful to stay on the main road. There are several turns that you may accidentally take if you weren't paying attention.