Which ports need plugged to do 850 carb synch???

[Guest]

Guys. Getting ready to synch my carbs tomorrow after work. Have done some reading and I am not sure what needs to be plugged to do the carb synch ??

Do I plug tank vacuum line ?
Carb vacuum port ?
Airbox drain hose ?

I am not familiar w CV carbs on my new 82 GS850GLZ. I have synchd carbs on my CB 750 many several times but carbs totally different. I am baffled by all the dang hoses on this bike.

Thanks for your comments.

Btw. Already did valves and carb clean.

Gary

[tkent02]

carb vacuum port.

This .

[Gary_t200]

Last question.
Is the air box large rubber drain tube supposed to have a plug in it ?? Mine does not

[JTGS850GL]

No, the drain hose stays open all the time

[Steve]

Sounds like you have had in interesting past synchronizing carbs. The basics remain the same, regardless of what carbs you have.

- You must have a line from each intake tract to a vacuum gauge.
- Since there is a vacuum port on #2 carb that goes to the petcock, plug it, unless you have really long hoses going to your tank, which is probably sitting on the bench a few feet away.
- You do need a fuel source of some sort. It's possible to use your tank that is sitting on the bench a few feet away, but you need a long hose. Most here use a temporary tank of some sort, many examples can be found in the archives.

There are really no other hoses involved. The vent hoses that are between carbs 1&2 and 3&4 should be connected and routed as they normally are. The breather hose from the top of the engine to the airbox should be connected and routed as normal. The airbox drain hose should be routed as normal. The safety drain from the fuel level gauge on the tank will probably still be connected to the tank, so that is not a problem, either.

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[mrbill5491]

Last question.
Is the air box large rubber drain tube supposed to have a plug in it ?? Mine does not

The new replacement tubes have a removable plugged now, so guess it is up to you whether to plug it or leave it open. I left mine plugged.

[JTGS850GL]

I'm confused... What good is a drain hose if it's plugged?

[Steve]

I'm confused... What good is a drain hose if it's plugged?

It's more of a "catch reservoir" that you need to empty periodically, like when you change the oil.

Having it plugged keeps any gunk from landing on the bike frame or blowing back onto the tire. It also pevents unwanted air from coming in.

I actually have two such hoses on my Wing that need to be emptied when I change the oil, so it's not exactly a unique concept.

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