I have never seen anything in the rules that you cannot exceed 60 degrees in normal cat.
Try BCAR Sect K, JAR23, EASA CS23.3, FAR Part 23.3
An aeroplane in the normal category is limited to non-aerobatic manoeuvres, which include
"Lazy eights, chandelles, and steep turns, in which the angle of bank is not more than 60 degrees."
The utility category is for limited aerobatic operation and permitted manoeuvres include
"Lazy eights, chandelles, and steep turns, or similar manoeuvres, in which the angle of bank is more than 60 degrees but not more than 90 degrees."