If you are exploring possible destinations for your next motorcycle trip, the Black Hills of South Dakota is a great one to consider. I have ridden there three times and enjoyed every one.
There are many great routes to ride and almost all the roads are in great shape. I think the best plan is to stay at one of the many nice hotels or inns in the area and take day rides. There is just too much to experience on a ride through. Scenic day route maps are available at many of the merchants around the Black Hills area.
One of the most scenic routs is through Custer State Park. The wildlife loop. Take the Needles Highway to the loop and exit the loop heading North on highway 16A. This makes for an awesome view of Mount Rushmore as you ride through the tunnels heading back toward the town of Keystone.
Another great day trip is the Devils Tower. There are great roads to and from the tower. You can go North after visiting the monument and gift shop to Alzada in the Southeastern corner of Montana. Take US highway 24 North to Hulett and get on 112 also called Hulett-Alzada Highway. This route really gives the feel of Big Sky country.
Badlands National Park is East of the Black Hills area but easily within riding distance. Take highway 44 East out of Rapid City. There are two small towns that are worth stopping in along the way. Scenic, SD is a ghost town West of the park. It has old store fronts and an old outdoor jail that is great for photos. Interior, SD is at the SE entrance to the Park. Stop at the Cowboy Corner gas station and general store to fill up your tank and grab something to drink. If you go during the summer you will need the drink. It can get very hot traveling through the park.
There are plenty of other less famous roads that are very scenic and plenty twisty. The town of Nemo is not much of a destination but Nemo Road is a great ride.
When looking for a place to stay consider Mountains to Prairies Bed and Breakfast in Hill City. It's on Main Street but the guest rooms are away from the road so it's not too loud. It's within walking distance of many restaurants and shops. Sam, one of the owners, knows much about the interesting history of the area.
The elevation in the Black Hills is about 4500 feet so the weather in the area can change quickly. I got caught in a hail storm that deposited 3" of the stuff on the road. Luckily I came upon the area AFTER the hail had fallen. It was a beautiful day up until that point. A local in Deadwood told me that hail storms do happen a couple of times a summer.
There are many historic towns in the area. Rapid City is the largest city in the area. Lead and Deadwood are old mining towns located next to each other not far South of Interstate 90. Sturgis is to the North of I90 and is a sleepy little town most of the year. The 1st week full of August is a different story. That's when the Sturgis Motorcycle Rally comes to town.
There is a reason that the biggest motorcycle rally in the country has been held in this area for the last 75 years. The riding is great!