• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

gs750 carb help!

  • Thread starter Thread starter horror1972
  • Start date Start date
H

horror1972

Guest
Hi,

own a gs750 '78
rebuild the carb with a keyster kit.
tried to adjust the jets with a colortune, couldn't get a maroon blue mixture, found out the air mixture(?)jet made a very small difference but the bottem jet didn't make any differnce at all.
the spark plugs are very black, so there's to much gas.

What does the bottem jet do? what does the side jet do?

what's the stock setting?

anyone can explain why yhe spark plugs are black?

please help!

regards,

marcel
the Netherlands
 
First make sure you have a clean air filter before attempting to sleuth out jetting problems. A filthy air filter may look clean, but it will make things run richer than you think!

Once you have fixed that, then see how it's running. I'm not saying that you don't have jetting problems, mind; it's just that we must start with the basics.
 
ok, found the carb-rebuild pdf on this side, great!
I'm gonna check the carbs agian.
What part of the keyster shouldn't I use?
 
ok, and gonna clean the filter, set the pilot jet to 1 turn and the air jet to 1 1/4 turn.
Let you know ..
 
ok, and gonna clean the filter, set the pilot jet to 1 turn and the air jet to 1 1/4 turn.
Let you know ..

Sorry but I don't understand when you say you have set the pilot jet to 1 turn? My understanding is that both the main jet and the pilot jet are not adjustable - they should be fully seated into the carb body. The air jet is the only adjustment other than sync and idle speed.
 
He means the fuel mixture screw, and the air mixture screw respectively, which are found on VM carbies.
 
yes, sorry, tfb is right, did mean the pilot air screw and the pilot fuel screw, :)
Gonna try tomorrow, since it's raining now and my garage is full :)

Anybody ever tried the keyster kit?
I noticed the jet needle is slightly different ,but looks similair like the one at: http://www.thegsresources.com/files/vm_carb_rebuild.pdf
My original is a bit thicker at the bottem, but anyway, it shouldn't make any difference at idle, low rpm.....
 
General thought is to reuse your stock jets unless you have a reason to change. The Keyster kits are somewhat generic and the jets do not always match what was in the carbs origionally.
 
Sorry for late reply,
anyway, all tnx for replies.
seems the previous owner tried to rebuild, but forgot to mtighten the choke plungers....
also set the float height to 24 mm and used the original mainjets.
Bike runs fine again.

Thanks
 
That's good news! Seems to be no end of basic problems that you can inherit with a motorcycle, eh.
 
Back
Top