• 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.

popping in the exhaust-carbs?

  • Thread starter Thread starter bubby
  • Start date Start date
B

bubby

Guest
how do i know witch carburetors are on my 77 gs 750 i know they are not stock the are stamped with MIC on 1 side Mikuni on the other and the identification number is stamped 217 with a 0 under neath it so im assuming its 2170.. my service manual says it should be stamped 45013 and it shows a 3 bolt oval top and a 4 bolt square top. the 2170 mikuni is a 2 bolt top and has the sync adjustment in between the carbs for sync adjustment. also im getting a pop in the exhaust around 3,000 rpm no matter what gear im in and a occasional pop with the choke on during warm up. i have checked and all exhaust flanges are tight and have no leaks
 
Last edited:
Can you post a pic of a carb? Mikuni and suzuki probably used different numbering systems, but maybe a PO changed them. Originals were VM style (oval top)
 
picture of the carb these are 2 bolt caps the ones in the book show a 3 bolt oval and 4 bolt square my book also show the sync adjustment inside the cap on these carbs its in between the carbs
 
Last edited:
no i took the pics with my phone and it switched the photo when i e-mailed it to my self to upload it here lol cap on top bowl on bottem like any normal motorcycle carb
 
Sorry, can't anwer what I can't read.
icon_shrug.gif


.
 
VM carbs! and now that computer stuff has been mastered, you still want to know in what order to sync them?
 
ive already synced them i was wondering what model they are i belive they are the reson im getting a 3,000 rpm pop ocassional hesitation and my bike has to have the choke on for like 15-25 minutes and it will still die sometimes when im at a red light i've adjusted the idle screw on a daily basis and i just cant get them dialed in
 
Synching the carbs is the LAST thing that needs to happen, after adjusting the valves and CLEANING the carbs thoroughly.

If you have to have the "choke" on for more than a minute, something is not cleaned or not adjusted properly. It is recommended to clean first.


What couldn't I read?
Just the single, incomplete, run-on sentence in the first post.
icon_shrug.gif

No, we are not grammar police, but that post is VERY hard to read.

.
 
sry im bad with grammar and run on sentences. Let me start over lol I bought the bike it did not run. i put new points on it, reshimed the valves, cleaned the carburetors, adjusted the air fuel to 1 and 1/4 turns out synchronized the carbs and this is what i got a bike that idles poorly and is cold blooded and like i said it pops around 2700-3200 rpms ........ my compression gage only goes up to 100lbs and all 4 cylinders max it out.... has good acceleration and runs its best over 3600 rpms hope this helps you help me lmao
 
Last edited:
Sorry, I am similarly bad with bad spelling, bad grammar and TEXTING. :rolleyes:

You say you have "adjusted the air fuel to 1 and 1/4 turns out". How far out is the FUEL screw? How far out is the AIR screw? If your fuel screw (the one on the bottom of the carbs) is not out far enough, it won't really matter how far out you turn the air screw (the one on the side of the carbs). "1 1/4 turns out" could possibly be a correct setting, but would require the fuel screw to be turned about half that amount, or 5/8 turn. Generally speaking, for a stock bike, the fuel screw should be about 3/4 turn out, the air screw should be close to double that, as a starting point. Slowly adjusting it from there to acheive best idle speed will determine its ultimate setting.

.
 
The air screw in your photo of carb #1,and #4 is way more than 1 1/4 turns out. At 1 1/4 turns, the screw head is still in the beveled area. You look like you are more than 2 1/2 out. Some of it could be camera angle, but the last picture looks like the screw is ready to fall out.
 
Last edited:
Those aren't stock VM26SS carbs either. Perhaps VM28 or 29 smoothbores maybe? Popping on decel is usually a symptom of an intake leak. Likely the orings behind the intake boots on the engine, dried out and rotten seals in the airbox etc. or an overly lean mixture particularly in the pilot and needle transition area.

Those look absolutely filthy by the way. I'm. It sure how you cleaned the carbs but it likely wasn the "correct way" to do it.

By the way, do you have a manual for your bike? And is it the correct manual? You keep posting questions that don't pertain to your model.
 
You must log in or register to reply here.
Back
Top