Ipl show it has a clutch setup though it is the first I have seen that the clutch drum is part of the front starter cover. I would check the flex cable for damage since that is a curve shaft model.
It also show it having a Ruixing carburetor which here we can't get parts but it look like you Aussies can. All we can get here is the complete carburetor but it is fairly cheap at 16 usd plus shipping.
There shouldn't be a flat spot in the acceleration so either the fuel needs adjusting or the carburetor rebuilt.
Ruixing RX-HR Repair Kit The following IPL link should give you the idea how the parts are laid out though it don't give part numbers. Looks they are trying to force you to buy from them.
Homelite HLT25CNB Spare Parts
