What's With The Polit Jet Cap Plug?

[Anonymous]

I just tore into a set of carbs on a 1981 GS650L. Pretty black and gummy in the jets. I have worked on a number of bikes and have never seen a plug covering the pilot jet hole like in the GS650L. Why is this? How is fuel
supposed to be drawn up through the pilot jet if it has a plug covering it? This is the one inside the carb that you can see when you remove the float bowl. As I understand it, fuel is sucked up through this jet. What am I missing here? Has anyone removed these plugs? They are easy to remove to access the jet. What happens when these plugs are removed?

Another question. What is the purpose of the air jet on the side of the air
intake on the filter side? Is this to allow a certain amount of air into the choke circuit? I have not seen this before either. It looks just like a main jet however no fuel goes through it, just air.

Thanks in advance.

Keith

[Detman101]

I wondered the same thing...

:?
Dm of mD

[SqDancerLynn1]

It's part of the mfg design The jet does not draw fuel from the tube The rubber plug seals this passage but still allows the jets to be removed for cleaning

[Redman]

Zuki manaul has diagram of the air flow and fuel flow of each system in the carb. The slow speed, the main/high speed and the starter (choke/enricher). I dont have much experience with this, just what I know from the Zuki manual.
It shows the fuel flow in the slow speed going thru that pilot, but first it comes up thru the main jet (in center, lowest point). There is a passage way above the main jet going over to the pilot. So I quess that is why the plug is required.
Says : "Slow system...when throttle closed or slightly opened..... fuel from float chamber is first passed through main jet and then metered by pilot jet where it is then mixed with air from the pilot air jet".
Pilot air jet is the one on the left. Is bigger than one on right which is the main (high speed) air jet.

[Anonymous]

I saw a set of carbs put together without those plugs. It started right up, would rev perfectly, when not under load, but when you put it in gear & try to pull away, the bike would just die, dead as a hammer. The guy scratched his head, till he saw those four little plugs laying there. Pulled the bowls, put the plugs in, and everything worked perfectly. I'm not sure what they do, but whatever it is, they've got be there.