Coat the birds evenly with olive oil, mix the salt, pepper, garlic, rosemary, thyme and optional red pepper flakes in a bowl and season the birds on all sides. Using butcher's twin, tie the drumsticks together. Then, tuck the wings behind the body to keep them tight against the birds and place in the refrigerator for 4-6 hours.
Light your grill. Set up the coals or wood to burn on one side. This should be away from where the rotisserie will spin.
While the coals are heating, take the hens out of the refrigerator. Place them on the rotisserie spit, making sure they are held tightly together by the rotisserie forks.
Pro Tip*When putting the forks on the spit, try to get them around the flesh of the bird as opposed to piercing the skin. This will hold them in place, without them losing any juice from rotisserie forks.
Coat the surface of the birds with remaining olive oil and put the spit into the rotisserie motor. Ensure the birds are spinning over indirect heat.
Allow the hens to spin for 60 minutes, or until they reach your desired internal temperature and the skin is golden brown and slightly crispy.
Using heat resistant gloves, remove the spit from the grill, and allow the hens to rest for 5-7 minutes before removing them from the spit.