help!

[hardley davidson]

I recently picked up an 83 gs750es an im having THE WORST time getting it running. It was in non running shape when I got it, and still is 3 weeks later. so far i rebuilt the carbs with rebuild kits and ive been through them 5 times. new spark plugs, new battery, fresh oil. getting spark to all 4 (but its somewhat weak looking) good compression to all 4.
bike will start up on full choke and race really high and sound really rough, give it throttle and it makes sucking sounds and it dogs down, or dies if i keep the throttle turned. (it didnt come with the airbox and its running k&n pods) when it warms up I can get it to idle at around 1800 but still sounds rough and intermittantly dies with throttle, or will die if left idleing for more than a couple minutes.
When I cleaned the carbs I dissasembled, soaked them in berrymans chem dip, washed them out with hot water, and blew through each and every passage with compressed air. (each time) I have the floats at 1.1" as per spec and the air fuel mixture screws at 1 3/4 out. i hooked my gauges up and the carbs seem balanced.
Im usually a fair wrench and can figure these things out, but im starting to throw tools and rip what little hair i have left out. any advice would be greatly appreciated!!!!!!!

[Steve]

1. How long did you soak them in Berryman's?
2. Why are the floats set to 1.2"? Spec is 22.4mm, which is .88". Floats at 1.2" will make it run lean.
3. With mixture screws at 1 3/4, it will run even leaner.

If carbs were not dipped long enough, crud might not have been softened sufficiently for you to blow it out. If you don't know ALL the little passages to blow out, it's real easy to miss the important ones.

Raise the floats to the proper level (which is a lower number on the float height measurement), it will be a better baseline for ALL the carb circuits.

I like to start with the mixture screws out plenty to ensure a rich mixture for starting. When the bike is warmed up, I will sync the carbs and tune the mixtures. I start with the screws out three full turns. By the time the screws are tweaked a bit, they might be in the 2 to 2 1/2 turn range, but 1 3/4 is just lean enough that it will not idle nicely, especially since the fuel level is low, due to the float height.

One more thing, are you starting the bike correctly? Apply "choke" (amount will vary, depending on your bike), turn the key, pull the clutch lever (unless you have bypassed it), push the starter button. Adjust cold idle speed with the "choke" control. Did you notice that NOWHERE did I mention "move the throttle"? That is because you should not do it. While the engine is cold and running on "choke", ANY application of throttle will destroy the high engine vacuum that is necessary for the "choke" (actually an "enrichment circuit") to work. Until the engine is warmed up and the "choke" is turned off, yes, your engine will make some sucking sounds.

Get the mixture properly richened up so the bike will run, you will be able to get it off "choke" in about 30 seconds, and will be on your way that much quicker.

.

[rustybronco]

You have to ask yourself, "is the bike properly jetted for pods?".

http://www.mtsac.edu/~cliff/storage/gs/GS750E-ES_Shop_Manual_1983.pdf

http://thegsresources.com/_forum/showpost.php?p=1355236&postcount=154

Carburetor Information For a 1983 Suzuki GS750ES


Carburetor Type: MIKUNI BS32SS
Bore size: 32 mm (1.3 inch)
I.D. No. 06A00 (06A10 for CA)
Idle r/min. 1,150 ± 100 r/min
Fuel level 5.0 ± 0.5mm (0.20 ± 0.02 in)
Float height 22.4 ± 1.0 mm (0.88 ± 0.04 in)
Main jet (M.J.) #122.5
Main air jet (M.A.J.) 1.7 mm
Jet needle (J.N.) 5C-28
Needle jet (N.J.) Y-5
Pilot jet (P.J.) #37.5
By-ass (B.P.) 0.8, 0.8, 0.8 mm
Pilot outlet (P.O.) 0.7 mm
Valve seat 2.0 mm
Starter jet (G.S.) #45
Pilot screw (P.S.) PRE-SET
Pilot air jet (P.A.J.) PRE-SET
Throttle valve (Th.V.) #135
Throttle cable play 0.5 - 1.0 mm (0.02 - 0.04 in)
Choke cable play 0.5 - 1.0 mm (0.02 - 0.04 in)

[chef1366]

These CV carbs won't run for crap without an airbox.
Get a jet kit from Dynojet or Factory Pro if you are going to run pods.
Replace the o-rings behind the intake manifolds.
Seperate the carbs from the rack, strip down to bare bodies and soak the metal parts in Berrymans. Don't miss the idle-mixture screws and they also have an o-ring.

[BassCliff]

Greetings and Salutations!!

Hi Mr. hardley davidson,

There is a lot of information in the links below. Read it all carefully and follow the maintenance lists and the "how to" guides properly. Skipping steps or taking shortcuts will lead to frustration at best, tragedy and mayhem at worst. Below is what I call the "mega-welcome".

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Please Click Here For Your Mega-Welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

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Thank you for your indulgence,

BassCliff