Hi Grumpy, having a bit of trouble understanding whats happening. Will try to explain it with pictures from link you provided.

When i spray carby cleaner into the main air bleed ( pink hole ) it comes out the bottom of carby body via the " white hole ". (picture two )
When i srpay it into the bowl vent ( blue circle ) it come out the bottom of carby via green holes. ( picture 2 )
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