2: King John's last to find out (5)
3: Northern state nominates radical (9)
4: Sounds like a bright child (3).
5: Caesars standard golf score? (5)
8: Principle unaffected by revolution (5)
9: Frost over mid-January during epic exploit (3,2)
11: Bloody bored inside (3)
13: Sister gets nothing, we hear (3)