Fast Idle Issue

[Rudi]

Friends,
I can't seem to find a thread to help me with a particularly irritating problem. I finally got my new (to me) 1980 550 up and running...yesterday she was idling perfectly at about 1200, today she is at 4k and the idle adjustment screw is spinning freely with no effect. Two questions:
1) If my idle adjustment screw (brass bugger up-side-down in the middle of the carbs) is spinning freely without bottoming out or coming loose, what does that mean? (Is it stripped out, is it mechanically limited, etc?)
2) How would you begin trouble shooting the problem?
I'm the worst possible combination of a newbie and not terribly bright so bonus points to anyone who can offer advice that is accessible to a fruit fly with ADD (that would be me.)
Regards,

Rudi

[Calvin Blackmore]

id say yer throttle cable is hung up somewhere
holding the throttle open and preventing the bit that is moved by the idle adjuster form getting within range

[Rudi]

Sounds like a fair place to start...I'll look into it. Any ideas about why the idle adjustment screw is wonky?

[Calvin Blackmore]

Sounds like a fair place to start...I'll look into it. Any ideas about why the idle adjustment screw is wonky?

you mean freely spining ?

it should have a spring to keep tension on it
I have not seen one that didnt

[Rudi]

you mean freely spining ?

it should have a spring to keep tension on it
I have not seen one that didnt

Unfortunately, it looks like I may have a first (that is, an adjustment screw without a spring.) On the bright side, that may well explain the problem. It looks to me like the throttle cable is alright. Dr. Blackmore, I hope you have a long and happy life...thanks for the help.

[Nessism]

Intake boot O-ring leaking.

[Rudi]

Intake boot O-ring leaking.

Nessism,
Hmm...This sounds pleasantly manageable. So let me display my ignorance. I've found what appears to be the air intake under my seat (as it were). I get the strange feeling that this isn't what we're talking about though because a leak here would hardly be a problem. I'm guessing the intake boot-a-ma-bob is in the carburetor itself. Using little words (aware that I am both dense and without a manual at present) how should I go about evaluating this? Any guidance would be most appreciated.

[Ohioan]

intake boot = rubber thingy between carbs and the engine. Unscrew those, and there is an o-ring there. Replace boots and o-ring.

www.cycleorings.com is your source for those o-rings.

[Rudi]

Uh...Did I kill something?

So...I decided to replace chain and sprocket first because that seemed more manageable and it had to be done. I've got the drive train sorted, so I thought I'd fire things up to see how they run. As soon as it fired it began pouring gas out of the rubber hose that is apparently coming out of the mysterious intake boot.
Does this confirm the previous diagnoses or have I managed to destroy my bike before I even got started? Any advice would be most welcome - just note that I have a wee little brain so short words and simple explanations are best.

[Nessism]

Any advice would be most welcome - just note that I have a wee little brain so short words and simple explanations are best.

What maintenance have you done?

[Rudi]

Ah...

That's the strange part, this is new behavior, but so far all I've done is:
1) Replace the battery
2) Replace the sprockets (cover, etc. are still off, but do not seem to be connected to the problem.)
3) Replace the chain
4) Replace the air filter with an OEM filter that came with the bike

I did hook up a carb tuner to the little ports nibblets, but all appeared to be fairly well balanced.

Please feel free to let me know if this is simply a waste of your time - at some point here, I think I'm going to have to start at the gas tank and the air intake and walk through the whole system just making sure that hoses, the petcock, o-rings, carbs, etc are all functioning.

Thanks for the interest.

[Nessism]

Please feel free to let me know if this is simply a waste of your time - at some point here, I think I'm going to have to start at the gas tank and the air intake and walk through the whole system just making sure that hoses, the petcock, o-rings, carbs, etc are all functioning.

Thanks for the interest.

No GS bike leaves my garage until it's had all this stuff done. Until you do all the basic maintenance you never know when the bike will break down next.

[mike_of_bbg]

I did hook up a carb tuner to the little ports nibblets, but all appeared to be fairly well balanced.

Did you get those sealing screws back tightened in pretty well? Leaking air through those will easily get you to 4k. Ask me how I know

[Rudi]

The Forum Helps Again

Friends,
A couple of thoughts. First, my problem appears to be identical to the problem on this thread Looks like I'm getting ready to replace some o-rings and check out the floats.
Second Mighty Mike of BBG (Please tell me that's the Brooklyn Botanic Garden) - I'm definitely going to look at tightening things up a bit.
Just for the sake of clarity, I am a COMPLETE moron when it comes to all things fuel related and I am scared spitless that I will destroy the old girl when I try to fix her carbs...Rest today, work tomorrow, destroy my bike on Tuesday. At least I'll have a good group to come crying to when she's in pieces on the floor and I'm utterly lost.
Regards and thanks for all the good guidance.

Rudi

[Steve]

Sounds like you are in need of some experienced eyes.

In which corner of oHIo are you hiding?

There's a BUNCH of us down in the bottom-left corner, just give a holler.

.