GS1100E petcock

[suzukiSam]

Ok, folks..

Here is a pic of the petcock on the tank of my 1980 GS1100E. Is this the way it should be, or is something amiss ? (aka, missing).

[tom203]

You likely got the deluxe "leverless" 1980 petcock- has many interesting features.

[suzukiSam]

suhwheet.. so its all good then.. thanks.

[mvalenti]

You likely got the deluxe "leverless" 1980 petcock- has many interesting features.

like self cleaning.....

[tom203]

like self cleaning.....

Hmm, that wasn't one the features I was refering to.

[hampshirehog]

Light weight? Streamlined? What else could you have been thinking of...?

[tom203]

Light weight? Streamlined? What else could you have been thinking of...?

I was thinking it wouldn't snag my shoelace when I hop off!

[the erastus]

There is good reason this type petcock was in service for only a short time.

[suzukiSam]

keep typing.. I'm reading....

[sedelen]

The fact is it's a very unpopular petcock. You have to use a screwdriver to switch it from "On" to "Prime" and hope your fuel gauge works as it doesn't allow for a reserve function. Maybe someone more familiar than me will come forward with the recently posted diagram of the switch positions and their functions.

[suzukiSam]

well, here's the deal.. I'm prepping to start this bike up, after its been sitting for over 10 years.. My previous bike was a BMW K-bike with fuel injection, so this petcock thing is new to me.

do I need to do anything with this PC, when starting the bike ?

[Tom R]

It has a prime function, but in my experience it probably won't work since it's dependent on a 32 year old rubber check valve to hold the diaphragm open once you bump the engine. Be prepared to take a pull on it to apply vacuum to the petcock and fill the bowls.

[sedelen]

There is a '80 GS1100E owners manual on BassCliff's web-site. It does show the leverless petcock on page 18 and shows the "proper" position which matches your picture, so whatever other position it will turn to must be the "prime." Prime allows the fuel to flow gravity feed style, it is supposed to be used to "prime" your carbs after the bike had been sitting for a spell.
You can start and run it in prime, but don't leave in it in prime with the engine off as it could cause your carbs to overflow and get gas into the cylinders and your oil. Ask me how I know?
Here's your owners manual.

http://www.mtsac.edu/~cliff/storage/gs/GS1100E_Owners_Manual.pdf

[Tom R]

That would make sense, but this petcock has a small air bleed that's open in the run position and closed in the prime position - that is all turning the leverless lever does. Theoretically, when the air bleed is closed in pri position, the diaphragm will remain pulled down after you bump the engine to create some initial vacuum.

[suzukiSam]

ok, bike is not starting. I've got spark, and I manually fed some gas into each spark plug chamber, re-installed plugs, turned it over, and it fired up
for a short duration.

I'm not getting fuel to the carbs.. I removed the tank/hoses, and
extended the larger fuel hose (gas line in) directly into a can of gas, and
the smaller hose (vacuum) as well. (eliminating any probs with tank petcock)

Turned the engine over, and no go.. I'm not getting any vacuum/suction..

Any ideas what I should check/test next ?