Announcement

Collapse
No announcement yet.

Screwed-up carb:1 Me:0

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    Screwed-up carb:1 Me:0

    I've owned a 1982 GS650 for a few months now and would love to know how it rides! When I bought it the bike would start up and idle decent and when I would apply and release the throttle the rpm's would rise and continue to rise even after releasing the throttle. Fearing redline, I would put a stop to this by playing with the choke. Shortly after gaining control of the rpm's again the bike just cuts off and won't start for another 5-10 minutes. When I can get it to run there is about a 1 second lag in throttle response. There is also some predetination going on that pops the carbs around a little. The bike doesn't seem to want to run longer than five minutes.
    So, I rebuilt the carbs as I daydreamed of all the places I would drive to: the bar, the beach, the bar, all the fun places, only to have the same ___ thing happen. I mean, it ran no different than it did before I rebuilt the carbs. Please don't laugh, this is hard enough to admit as it is. I used K&L kits and set the bowls as best I could. I rebuilt the edelbrock carb on my 71 Nova with perfect results, so I don't understand what went wrong. Couldn't find any vaccum leaks, played around with the air screw and could not get any good results from any screw settings. If anybody has any suggestions I would love to hear them!! Thanks for your time!
    Tags: None
    #2
    Adam & Evils runaway carbs

    What are the color of your plugs? Also, are they wet? Dry?

    Detonation through the carbs sometimes indicates leaky valve....which can backfire back through the intake valve and consume the gas coming in....affecting starting. How's compression? Bike crank over evenly? It should. Cam timing correct? What makes you think it is the carbs?

    Comment

      #3
      my carbs

      Thanks for the reply and sorry for the delay (I was at the beach). I checked the compression when I bought the bike and had good readings, all were a consistent 125 or so I believe. This would lead me to believe that cam timing is, for the most part, correct. Throw in the fact that the bike does turn evenly with the starter and I have to find fault with the carbs. Also, the bike will run with the addition of a little starter fluid. And too, I should mention, that I get good spark from the plugs.

      Now the plugs aren't going to win any beauty contests, they have a decent coating of carbon and two are a little damp with oil I believe. Again, they still spark up.

      Oh, by the way, the engine has around 33K on it.

      One thing I'm not certain about however, is the setting for the mixture screws. I tried all the settings through 1 to 4 turns away from bottom. Still could not get any good results.

      Hope I can get it running soon before it gets too cold.

      Comment

        #4
        pic of bike

        This is my motivation. I'm not sure if the link will work but, hopefully it will be a picture of my bike.


        [/img]http://home.earthlink.net/~adamn79/images/gs650.jpg[img][/img]

        Comment

          #5
          Some wet, some sooty? You got some mix problems.

          You say you cleaned them... what guidelines did you use to put them back together? Try rechecking float levels, screw settings, and hoses. Also double check the intake boots and the airbox for a good seal, as this GREATLY effects the gs650.

          Comment

            #6
            carbs

            I didn't think about the air box causing a problem. I'll have to check on that. I referenced a clymers manual for rebuild (not too helpful) and some of the material here on this site. The only thing that has the ability to be adjusted is the float height and the mixture screw, so I don't see how I could have botched that up. I know the boot seals are good and I think the air box is too.

            I really need to find out what the setting should be for the mixture screw. At least a base setting to make adjustments from.

            I am also not sure if someone put in too big of jets. I don't know what the factory jets should be either.

            Thanks for your help so far!!

            Comment

              #7
              The airscrew, as a baseline, should come out 2 1/4 turns from seat. Seat it gently, or you can damage the seat!

              Also hand set the butterfly.. use a small diameter drill bit, and set the butterfly in each carb by closing it on that bit in each and setting it there. Po man's symcronize, will get you in the ballpark and make everything else easier.

              Comment

                #8
                butterfly

                Thanks for the advice!! I have a question though...what size of drill bit do you consider a smaller bit? What may be small to some may not be to others. 3/8"? 1/8"? Also, I am unfamiliar with the butterfly. I can't think what this would be. Thanks again!

                Comment

                  #9
                  The bike should have CV carbs, with a flat plate in the middle of the intake side. This is the butterfly valve, and is adjusted when you turn the screws outlined in the carb sync process.

                  Any tiny bit will do. Frankly, I eyeball it and didn't look at the size. SMaller than a wire coathangar, about the size of good bailing wire. The key is setting them all to a base setting that is the same, more than accurate... a sync will take care of that.

                  Comment

                    #10
                    butterfly valve

                    Aaahhhh...I see! I will give it a try. Thanks!!

                    Comment

                    Previous template Next
                    Working...
                    X