Just checked, mines is an FZX 1414.
Looked it up on that link, it has:
Carburetter: FZX 1414 Total Carbs: 1
Make: Metro Model: 1000
Year: 1982 - 1982 Engine: 1000cc HLE
Set Part No: Type: HIF38
Is that my problem? The one you stated is for a 1300, mines is for a 1000!
Hmmm.... Is the HIF44 a 44mm body and HIF 38mm?
So ill at least have worse off performance than the HIF44..