1978 gs 750 carbs cleaned now the oil glass gauge looks black and over full.

[TheCafeKid]

I'm in agreement with Tom. Don't mess around with a 35 year old petcock.
Just replace it and don't worry about it for another 35 years.
I'm poor too, but when it comes to gasoline possibly filling and ruining my engine, or catching my balls on fire, I'm not messing around. I once tried to rebuild a petcock, and it worked for a few weeks. So then I was going to do it again and halfway through it dawned on me that having my sack on fire would probably not be fun.

As to your wobble, how old are your tires? And is this wobble completely new??

First thing I'd check (and I'd also advise simply replacing) is the steering head bearings. They over time will smash dimples into the races and then the bearings rocking in and out of those dimples will cause your wobble.
It's also a good idea to check/replace your wheels bearings. And if your tires are more than a couple (two) years old even if the tread looks ok, I'd suggest replacing those as well.
This is all as a matter of safety. The wheels and tires are the only things keeping you attached to the road...if they fail, you'll fail and it'll hurt.

[chuck hahn]

This IS A VALID TEST..TOM!! If its bad, the weight of the gas making pressure against the seal and simple gravity will make it leak. The weight of the gas against the seals will be much greater than any suction in a pop bottle or from the carbs for that matter.

[rustybronco]

This is the only grease that I use on steering head bearings: http://parts.cat.com/parts/machine-f...rt-gold-grease
About $10.00 a tube and lasts forever. Synthetic, of course!

Here's what I use---> http://royalpurpleindustrial.com/prodsi/upg.html I will last me a long time because I got a lot of it for free.

[1_v8_merc]

I use Ford moly for mostly everything.
If it's going to get wet, I'll use Marine grease.

[MoMakkawi]

thank you for the input will check when home tonight to see if i can find the problem. will post an update soon.

You guys are a great help, I would be stumped if not for this forum

[allojohn]

Just replace the damned thing. It's 35 years old already, you (or someone else) have gotten your money's worth out of it already. Several gallons of gasoline above a hot engine near a poor electrical system with 35 year old coil wires in between your nuts at highway speeds in heavy traffic is nothing to trifle with.

Wanna see some cool burn scars?

You are quite entertaining at times tkent02.

[tkent02]

This IS A VALID TEST..TOM!! If its bad, the weight of the gas making pressure against the seal and simple gravity will make it leak. The weight of the gas against the seals will be much greater than any suction in a pop bottle or from the carbs for that matter.

Right, Chuck.
The suction comes from the vertical drop, it can be MUCH greater than the tiny drop from the top of the tank to the petcock.
Try to read a little science, it's good stuff. Or at least try what I suggest before you **** all over it.
Better yet, just go back to the greetings.

[chuck hahn]

try a little common sense...it will get you farther than science.

[chuck hahn]

1 gallon of gasoline equals 5.8 to 6.5 lbs. Depending on ambient air temps. So that being said, 5 gallons X 6.2 ( as a medium value ) equals 31 LBS of collective weight above the petcock which is supposed to hold it back. Now that little itty bit of suction really isnt the over riding factor in a leak as compared to the collective pressure from 5 gallons of gas upstream. Im sure your degree in scientific "theory" will say otherwise though.

[tkent02]

Chuck, are you serious? You really can't figure out how this crap works?

Not only is your math wrong, it's the wrong math.

The volume doesn't matter, the vertical drop does.

Nevermind, I don't get paid to teach kindergarten physics to people who won't learn.

[7981GS]

The weight of the gas against the seals will be much greater than any suction in a pop bottle or from the carbs for that matter.

Daniel

[chuck hahn]

Yeah should say 31...so i typed that the wee hrs of the morning...so what. Pressure is pressure whether its from gravity forcing from the top or suction. My test will yield the same basic results as yours. I do as a man with 42 years as a mechanic tells me to do..not what some science page on the internet says. He knows more than youve ever forgotten about bikes and especially the GSs.

[chuck hahn]

Anyone mention the wheel bearings as a spot to check for that wobble???

[MoMakkawi]

well here she is with the new bars on, still not familiar with how to post pics better here. i found sucking through the vacuum tube that way to much gas was coming out.. so i am pretty sure thats the problem for overflowing. I have been searching online for a new petcock and have had no luck. Any one know where i could get a new petcock for my 1978 gs 750..

[chuck hahn]

What do you mean that too much gas is coming out? Its a 1/4 inch hole and its gonna gush out like a fire hose into the bottle. The floats (SET AT THE RIGHT HEIGTHS ) regulate how fast the flow goes thru each carb as each cylinder uses the gas from the bowls. As was stated before..check the float condition, the condition of the seats, and reset the heights on each of the floats in each carb. Have you done all this or just piddled with the petcock and assume thats the culprit? Not trying to bust your balls but you really need to check them.