Like Wolf Q with Nebo - Smokey gets going during play sessions, especially when he's on his back. I usually hold his muzzle closed and say "No Biting." Most of the time he comes back at me with his mouth open, will "mouth" my hand/arm and then licks instead of biting. (Praise)
But if he keeps going I ignore him and stop playing. He usually gets the message.
(By the way, Smokey is about 10 and a half months old)