Combine the kosher salt, black pepper, garlic granules, sweet paprika, and cayenne in a small bowl. Place in a rub shaker to sprinkle onto the rib roast.
Trim any excess fat, silverskin, or gristle from the rib roast. Evenly sprinkle the rub over the rib roast.
Light the fire for the rotisserie to a hot temperature.
Secure the rib roast to your spit as per manufacturer instructions.
Place the spit on the rotisserie to create a medium temperature and start rotating. Cook until done to your preferred liking; about 2 hours.Tip: There are so many variables here that any time is just an estimate. Factors to consider are the size of the roast, the temperature of the roast when you start cooking, the type of fuel used and heat it produces, lid or no lid on the rotisserie, and preferred doneness are just a few of these. It is best to use an instant-read thermometer to keep an eye on your preferred temperature.
When cooked, rest for 10 minutes then slice to serve.