I'm not having a go
The preface used immediately before having a go.
I'm not havin' a go at ya now, but dat's de worst lasagne I ever ate.
Shall I translate it into posh English for you, head?
Welcome, welcome! Here it is in posh English.
I intend no criticism whatsoever, but that is the most dreadful lasagne I have ever consumed.
Questions
What does I'm not having a go mean in Ireland?
The preface used immediately before having a go.
How do you use I'm not having a go in a sentence?
“I'm not havin' a go at ya now, but dat's de worst lasagne I ever ate.”
Updated
On the list: Irish slang phrases