Hi Grumpy, the way you have explained cleaning a carby is the way i do it, in one of my first post you talked me through it that way and done it that way ever since. But just to make sure did strip carby down and fully cleaned it again.
Did make a new gasket for side of carby, grey one, there was a tiny split in it were the air port is, other "split " was just a mark. Sad to report there is no change at all. Thinking out loud here, could it just be a sh#t carby.