Do you think that Jacob new there was a chance of him becoming a werewolf.

i dont think that he new that he was going to become a wolf because then he wouldnt have told bella that he would never leave her

Well Jacob new about the stories about his people... but wasnt sure thet were real until he felt the change in his body and i guess either Sam or his father explained to him about the werewolfs.

yes jacob did know that he would turn into a wearwolf