What do I do with this carb?

[patrick328]

Back when I thought the carb on my recently acquired 2001 ZX 50 Super Fever was questionable, I bought what seemed to be a direct replacement from ebay, here: http://www.ebay.com/itm/331080013158?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649.

It said Kymco ZX Super Fever, so I bought it.  Wrong Super Fever?

When I got it in the mail, it was obviously bigger than stock.  The good news is, I don't need it anyway.  But hey, it's bigger.  Correct me if I'm wrong, but if you can get a bigger carb to work, then that means more power right?  Or better throttle response?  It has to make something work better because it's bigger, right?  Anyway, the main question here is what do I do with the extra port on it?  They (stock and new) both have ports for fuel, oil, bowl drain.  But the new one has an extra one.  I looked up the diagram for the Honda Elite 50, since the ebay ad says it works on one of those, and it showed one of the hoses coming off its carb being a vent tube or something.  What is the purpose of that vent tube?  I mean, why don't they all have one?  Should I put a vent tube on this one or just cap it off?

One more question, is there anything wrong with deleting my stock air box and throwing on a cone filter?

[245luigi]

The vent tube is for the fuel bowl which requires atmospheric air in the airspace above the fuel for the venturi to work properly.

In theory you can remove your stock airbox and go with a cone filter, however this will require you to rejet and retune the carb for marginal performance gains. You shouldnt really think about going to a cone filter until you get a Big Bore Kit.

[patrick328]

Hey thanks!  But why does that carb require the vent while my stock carb does not?  Actually maybe it does and I just forgot, the scooter isn't with me right now.

[245luigi]

There is some sort of vent, there has to be for it to work. Some carbs do well disguise them. If you take your carb off and tilt it and fuel come out from a random place, there's your vent!