A mate of mine had to pull the jets out of his Kipor generator and clean them out. It now works perfectly and is not noticably louder than a honda of the same size. And it cost half the price.
There is some very low quality gear coming out of asia, and it is mainly driven by the fact that we all want to pay less. Some of us may be willing to pay more for better product, but we are a minority and that means lower turn over of stock which drives up the cost and stops the shop from selling the better gear.
We need to take inferior products back to the point of purchase to inform them that the gear is no good. I do understand your reasoning Far Side, it van be easier and quicker to fix it youreslf, and it may even work better then. But unless you notify te seller they can't do anything about it.
Brett