flying off in a few hours time. not very sure about the regulations.
from the changi airport website:
"In terms of size, the bag's length, breadth and height (including protrusion) must not exceed 115cm (46 inches) in total. For example, a bag with the dimension 55cm (L) + 40cm (B) + 20cm (H) will be allowed (L+B+H = 115cm). "