Have you balanced carbies yourself before? That is not too hard a task with a vacuum gauge.

Otherwise there are three workshops I know of, one I haven't seen the quality of workmanship yet.

First and best is ****.com but ******'s waiting list is out to months.

2nd is redline performance is Dandenong.

3rd is Ben Reed, ex GP racer has opened up a store in dandenong, specialising in two strokes from what I have heard. This is the unknown store.