• 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.

GS1000G 1980 BS34 CV Carbs - Lean Running?

  • Thread starter Thread starter gs7.11
  • Start date Start date
I ran a a 4 to 1 and k&n drop in filter. (80 1000g) Had a lean spot from 4500 on up.
I removed the the spacer completely, pulled hard all the way about 7500ish then i stepped up to a 125 main, then a 128 which then would pull hard to about 11000.
I had the screw at i think 3.5 turns. Some where in there.
To finish it off i should have gone back and added small shims to the needle to lean it out to a proper amount. But i didnt mind it a little extra rich. Also added some timing. Don't remember how much though
 
Nessism said:
There are many people with 1000G's here and running lean with them is not typically a problem. I've owned two different 1000S's which use the same head/pistons/carbs as the G, with just minor airbox differences between them, and neither of them was lean running.

Did you lift the needles yet? Realize of course that using a big bore kit may have some effect on the jetting. And if you are running a non stock air filter that could too.
Click to expand...

Thank you for the help.

So lean running is not a commonplace thing then. Which confirms I have an issue.

I haven't lifted the needles yet as I haven't had time, and don't want to sand down the spacers without being sure why I was doing it. I've also bought another set of carbs, which I can clean up and compare with the originals. I've also bought an Ultrasonic cleaner so will be trying that out too.
The air filter is stock.
I'm reluctant to think that the big bore is causing issues at low throttle/rpm as I've fitted quite a few and never had to make any changes before for other than WFO operation. I might be wrong, as I'm not arrogant, but inclined to look elsewhere first.
Thanks.
 
thebrandonbeezy said:
I ran a a 4 to 1 and k&n drop in filter. (80 1000g) Had a lean spot from 4500 on up.
I removed the the spacer completely, pulled hard all the way about 7500ish then i stepped up to a 125 main, then a 128 which then would pull hard to about 11000.
I had the screw at i think 3.5 turns. Some where in there.
To finish it off i should have gone back and added small shims to the needle to lean it out to a proper amount. But i didnt mind it a little extra rich. Also added some timing. Don't remember how much though
Click to expand...

Thanks.
My prob is lower rpm than that. Points to a pilot jet rather than needle?
The bike runs fine (enough, may need a dyno run to be 100% sure) at anything above half way, so I think the stock 115 main jet is good enough for now and shouldn't be interfering with mixture at below 4000.
 
I agree that your main jet is OK, but the lack of taper on the needle may be the issue.
The pilot/cutaway/needle jet/needle all overlap in that range
 
I have a stock 1000g and a V&H 12500 model pipe. I have 42.5 pilots and actually went a little lean on mine to 114 mains. That's what a lot of testing revealed to give best plug color at speed and overall perfect driveability. I have a tiny flat spot right at 2800 but it's not worth tuning over. I never touched the needles though it is probably worth trying aftermarket.
I went the big jet route for a few months until I got serious about testing. Wasted a lot of gas and dirtied oil. Learned to respect the test results, not theories of others.

Every bike is different.
 
Big T said:
I agree that your main jet is OK, but the lack of taper on the needle may be the issue.
The pilot/cutaway/needle jet/needle all overlap in that range
Click to expand...

Thanks :)

duaneage said:
I have a stock 1000g and a V&H 12500 model pipe. I have 42.5 pilots and actually went a little lean on mine to 114 mains. That's what a lot of testing revealed to give best plug color at speed and overall perfect driveability. I have a tiny flat spot right at 2800 but it's not worth tuning over. I never touched the needles though it is probably worth trying aftermarket.
I went the big jet route for a few months until I got serious about testing. Wasted a lot of gas and dirtied oil. Learned to respect the test results, not theories of others.

Every bike is different.
Click to expand...

Thanks. Useful feedback.
 
Well, if anyone is intetested, I found the problem:
Emulsion tubes.
In the end having tried absolutely everything, including Dynojet needles, removing vent pipes etc etc., I have ended up back at box stock jetting, unsurprising really with stock carbs and Airbox.

The emulsion tubes appeared ok, with no ovalling or other visible wear, but one I'd fitted new ones, it was immediately obvious I'd fixed it.
Hopefully this might be useful if anyone else has similar issues.
 
Well done.

Im really interested to know what it was about the old tubes that made the carbs not work.

Do they have the same number stamped on them? Do they look the same?

If it was me, I would be tempted just to put the old ones back in to see if the problem comes back. I know that sounds crazy but I would want to eliminate the idea that taking them apart and putting them back together wasn?t what fixed it. If indeed they are the same tubes (by number and manufacture) what went wrong with them?
 
You must log in or register to reply here.
Back
Top