• 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.

80 gs550 wont start (im sure its all been said before)

  • Thread starter Thread starter wolf
  • Start date Start date
W

wolf

Guest
i apologize for not searching harder to find the answer to my question in another thread, however i am extremely frustrated. i have a 1980 gs550 with good compression, good spark, good carb holders, rebuilt clean carbs and it wont start. seems like its all there right, well i do have modified exhaust and velocity stacks. i know these carbs are really tricky and need restriction but the slides dont even seem to flutter. when i manually lift them i still get nothing.

things i have done as to eliminate any redundancy:
cleaned and rebuilt carbs.
adjusted cam timing (fallowed a youtube video seemed legit)
checked spark... good
haven't used a compression tester but it sucks like a mother when you put your hand on the intake so i am assuming its good!
Also no tares in the diaphragms

here is my question.

1:shouldn't this thing at least start and what do i do if not?

2:will 70s mechanical slide carbs fit on CV intake? im sick of this crap!

any help is appreciated im about to set it on fire!
 
Last edited:
wolf said:
i apologize for not searching harder to find the answer to my question in another thread, however i am extremely frustrated. i have a 1980 gs550 with good compression, good spark, good carb holders, rebuilt clean carbs and it wont start. seems like its all there right, well i do have modified exhaust and velocity stacks. i know these carbs are really tricky and need restriction but the slides dont even seem to flutter. when i manually lift them i still get nothing.

things i have done as to eliminate any redundancy:
cleaned and rebuilt carbs.
adjusted cam timing (fallowed a youtube video seemed legit)
checked spark... good
haven't used a compression tester but it sucks like a mother when you put your hand on the intake so i am assuming its good!
Also no tares in the diaphragms

here is my question.

1:shouldn't this thing at least start and what do i do if not?

2:will 70s mechanical slide carbs fit on CV intake? im sick of this crap!

any help is appreciated im about to set it on fire!
Click to expand...

Get a bigger hammer, or learn how the carburetors work. They are good carburetors, most of them run perfectly with a little maintenance once every thirty years or so. Have you adjusted the valves? Where did you set the float levels? How about the mixture screws? Have you jetted the carburetors correctly for the intake and exhaust? What exactly did you do to clean the carburetors?
 
i have 42.5 pilot jets considering this is the start/low rpm circuit i assume it should start.

i did forget to mention i raised the slide needle .035

checked the valve clearance and they were all between .001 and .003

i did not set the float levels, are the main jets not suppose to be submerged because they are.

mixture screws started at 2 turns out after rebuild, then 1, then half, then bottom. i experienced minor differences between the adjustments

i soaked the carbs in chem dip and blew out all the passaged sans jets with 100 psi.

im assuming i will need to go to 100+ main jets to get it to run right but i used the stock 92.5s that came in the kit to see if it would even fire.

help
 
Fully charged battery, run fast (as in down the street), full choke, no throttle, key on, neutral, bump start in second. Try three times. Might be worth a try before the "fire" thing. I would think the mixture screws would need to be out at least a turn or two out from seated
 
wolf said:
between .001 and .003 is what the book calls for.
Click to expand...

.001 and .003 what? Miles?

CV carbs need restriction to work properly, that's what makes the carbs suck fuel. try duct taping over the stacks about 50%

You could rejet, but a Dynojet kit is likely in your future

Where that pods thread from Mr Cinders?

http://www.thegsresources.com/_forum/showthread.php?t=199275&highlight=pods


you'll find that whatever the problem you're experiencing. someone has posted it up here a dozen times before
 
Last edited:
Sounds like you need to start with the valves, then move on to the carbs, as has been stated you will need a dyno jet kit with the set up you are trying to run. If you want to just hear it run throw a set of 130 main jets at it and wire tie a folded rag over you velocity stacks. In order for CV's to work you need restriction. I am not saying this is going to be your ideal jet configuration but it is a starting point. Also have you replaced the o-rings in the carbs and intake boots? You could also go to the new members section and introduce yourself and receive your welcome package from Basscliff and spend some time reading. Pay particular attention to newbie mistakes. Also youcan download a factory manual and learn who your carbs work so that you can better understand them.
 
how do you mean start with the valves? i did timing and clearance checks. both check out.

valve clearance all between .001 and .003 of an inch as per service manual.

cam timing exhaust cam to intake cam 18 pins apart bot arrows pointing straight up a #1 pin and #18 pin.

did i not do something right?
 
wolf, the first thing you need to do is put units of measure when giving numbers. You finally put inches, which is a good thing. IDK what the book says in inches, as I use metric feeler gauges. Which is the second thing you need to do, get a set of metric feeler gauges. You own a metric bike, please treat it accordingly.
If you are using a Haynes or Clymers manual, please go to BikeCliff's website and download the Factory Service Manual for your bike (if you have not already done so). It is not rife with mistakes like the others.
You stated you set the cam timing. What exactly does that entail? Unless you removed the cams, I am not sure why you would need to do that. IDK what the book says the marks should be set to, so I assume you set them according to the Factory Service Manual.
You have an electronic ignition with a mechanical advance, so the ignition timing should not require an adjustment.
(With velocity stacks, you are going to have a devil of a time tuning the carbs. Just an FYI.)
However, it may start on the pilot circuit even with that handicap. Your mixture screws should start at 2 1/2 turns out for the initial startup.
You stated that you did not set the float levels. This is a must-do operation. Nessism's carb rebuild tutorial explains how to do this adjustment. That is what I suggest you do next.
 
koolaid kid, thanks that manual is telling me something different about cam timing. ill have a go at it tonight.
 
cam timing was off, tensioner wasn't functioning correctly and it allowed the chain to skip on the cam. retimed it and cleaned the tensioner and it fired up. now it wont idle but it fires. so im thinking 120 main jets.

mixture screws out 2 turns by the way.

thanks for all the help!
 
yes, i fallowed the manual. released the tensioner, turned the crank couter clockwise one turn and then forward.

seems to be working great.
 
It does not use the main jet to idle, it uses the mixture screws. How are they set? You should start with them 2 1/2 - 3 turns out. See the link in my signature for getting them set correctly.
 
i guess i was assuming it used the mains because the pilot circuit runs through the mains (with the pilot caps in). either way im 2 turns out and it seems rich actually... i have to have the throttle wide open for it to idle at all and it wont start with the choke on. the velocity stacks have a bit of restriction in them. so i will try leaning out the mixture and see what it looks like.

pilot jets are 42.5

thanks for the article, lots of help!
 
IT LIVES! 3/4 of a turn out and it idles. still needs some fine tuning for sure. thanks for all the info koolaid kid!
 
You must log in or register to reply here.
Back
Top