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    New issues: Carbs this time. I think.

    Thanks to everyone's help I now have my electrical problems resolved. Hd a bad coil. Replaced a good and a bad one with a bad and a good one: That's been taken care of. When I got the thing to start properly it wouldn't idle. Discovered that I'd turned the idle adjust screw WAY out. Now it idles.
    The problem is, it won't do much else.
    When I still had electrical problems I managed to ride the thing (once only) by bypassing the problem area with a hotwire. The carbs are newly jetted (Dynojet Stage 3) with K&N filters, and it ran like a champ. Briefly, until I took care of the electrical issues.
    OK. Now when it starts ? and idles beautifully ? it won't go anywhere. Warmed up it revs nicely to 6K (that's all I'm willing to give it, since it hasn't been ridden much in about 4 years), and very smooth throttle response.
    Put it in gear, give it some gas, and at about 1,500 or 2,000 RPM it begins bogging down. Tries to die. Feathering the clutch and gas, can get it to go, but it backfires at about 2,500 to 4,000 RPM, and won't rev past 4K. Stutters, backfires, slows down and croaks out.
    Restart it, idles nicely, get it home and park it and hope for some help.
    Sync the carbs, I assume. Timing? The manual (It's an 82 GS 650 E) says you can't adjust the timing. Is that a lie?
    I saw a GREAT explanation Earl posted May 17 on timing one with points, but Points I don't have. So now what?
    I do apologize for the long post, but I want to make sure someone with know-how also has the info to tell me what to do.
    Thanks,
    J. Daniel
    And as I said, the bike is running now for the first time (properly) in more than four years, thanks in great part to this most excellent site. Next project: Fork springs, seals, etc. But that will wait until the thing actually runs.

    #2
    Re: New issues: Carbs this time. I think.

    It still might be electrical. I'm not sure about the GS'es but some early 80's machines required a good battery for sparking. A friend of mine has an 84 Honda V45 Magna, if the battery is weak, it will idle but backfire like crazy when trying to ride it.

    You mentioned the carbs et. al. were done recently; how long ago? Has the gas been standing in the tank for long? My GS450 won't run right on old gas. My Clymer say the timing on my 84 gs450 doesn't need to be adjusted regularly but there has got to be a way to check it. A suzuki shop manual should list how to do it. Anyone else, feel free to correct me.

    hope this helps....Sam



    Originally posted by J. Daniel
    Thanks to everyone's help I now have my electrical problems resolved. Hd a bad coil. Replaced a good and a bad one with a bad and a good one: That's been taken care of. When I got the thing to start properly it wouldn't idle. Discovered that I'd turned the idle adjust screw WAY out. Now it idles.
    The problem is, it won't do much else.
    When I still had electrical problems I managed to ride the thing (once only) by bypassing the problem area with a hotwire. The carbs are newly jetted (Dynojet Stage 3) with K&N filters, and it ran like a champ. Briefly, until I took care of the electrical issues.
    OK. Now when it starts ? and idles beautifully ? it won't go anywhere. Warmed up it revs nicely to 6K (that's all I'm willing to give it, since it hasn't been ridden much in about 4 years), and very smooth throttle response.
    Put it in gear, give it some gas, and at about 1,500 or 2,000 RPM it begins bogging down. Tries to die. Feathering the clutch and gas, can get it to go, but it backfires at about 2,500 to 4,000 RPM, and won't rev past 4K. Stutters, backfires, slows down and croaks out.
    Restart it, idles nicely, get it home and park it and hope for some help.
    Sync the carbs, I assume. Timing? The manual (It's an 82 GS 650 E) says you can't adjust the timing. Is that a lie?
    I saw a GREAT explanation Earl posted May 17 on timing one with points, but Points I don't have. So now what?
    I do apologize for the long post, but I want to make sure someone with know-how also has the info to tell me what to do.
    Thanks,
    J. Daniel
    And as I said, the bike is running now for the first time (properly) in more than four years, thanks in great part to this most excellent site. Next project: Fork springs, seals, etc. But that will wait until the thing actually runs.

    Comment


      #3
      No, that's not it

      Thanks for responding.
      The battery is good. The carbs were cleaned about two months ago, and the jet kit was installed about a week later. Bike wasn't run in the interim, and has only been ridden 25 miles or so in the interim, on test runs (and to get it to my house from my brother's). The gas is good, only a few days (maybe a week) old.
      I've tried adjusting the idle using (maybe obviously) the idle adjust screw. Changed the idle, but didn't change the way it ran when in gear: still very badly.
      Tried last night to sync the carbs using mercury manometer. No luck. Never done it before.
      Cyl. 3, supposedly the base carb against which the others should be set, registered very little vacuum in the gauge. When I adjusted Cyl 1 up to about 16 inches, it brought Cyl. 2-4 up somewhat. Then I did No. 2 cyl, and #1 went up even farther, and the idle was speeding up, from about 1400 rpm to about 2K.
      After that I ran out of time and (since I couldn't understand what was going on) out of patience.
      I'm at a loss.
      Any further comment would be appreciated.
      J. Daniel

      Comment


        #4
        Re: No, that's not it

        ok, you've ruled out some of the easier type of issues.
        As for the synch troubles. I've used a mercury manonmeter on my old honda loads of times, it is tricky to use - a shop could do 4 carbs in ~30mins (not including time to remove the tank etc it takes me ~90min - gotta check things two or three times.

        Assuming its hooked up right and the idle speed was set prior to starting, check the attachment point for the card sync to carb #3. Sometimes spraying a little wd40 on the connection will help. If the vacuum changes when you spray then there's a leak there (the oil very temporarily lessens the leak) The other points to check would be the rubber boots from the carbs to the engine itself. If theses are all fine then I'm out of good ideas - only crappy ones left
        If I'm not mistaken its normal for the idel speed to change once the carbs have been properly sync'd. Also, as long as you get all 4 carbs within 1" or 1.25" of Hg you should be good.

        Hope this helps...Sam

        Originally posted by J. Daniel
        Thanks for responding.
        The battery is good. The carbs were cleaned about two months ago, and the jet kit was installed about a week later. Bike wasn't run in the interim, and has only been ridden 25 miles or so in the interim, on test runs (and to get it to my house from my brother's). The gas is good, only a few days (maybe a week) old.
        I've tried adjusting the idle using (maybe obviously) the idle adjust screw. Changed the idle, but didn't change the way it ran when in gear: still very badly.
        Tried last night to sync the carbs using mercury manometer. No luck. Never done it before.
        Cyl. 3, supposedly the base carb against which the others should be set, registered very little vacuum in the gauge. When I adjusted Cyl 1 up to about 16 inches, it brought Cyl. 2-4 up somewhat. Then I did No. 2 cyl, and #1 went up even farther, and the idle was speeding up, from about 1400 rpm to about 2K.
        After that I ran out of time and (since I couldn't understand what was going on) out of patience.
        I'm at a loss.
        Any further comment would be appreciated.
        J. Daniel

        Comment


          #5
          yes, yes, yes

          OK, I'll give the WD-40 spraying a try, see what happens. I hope to have time tonight for this. I'm sick of not riding.
          Just a note: There's significant valve racket inside: Doesn't sound like anything's broken, but I intend to adjust them sometime this weekend if possible. Any chance the running difficulties are caused by valve adjustment? Or am I grasping here?
          J. Daniel

          Comment


            #6
            Syncing up the carbs should be the LAST thing you do. Check timing and adjust your valves first.

            Comment


              #7
              Good to know. But one of my questions was whether it's possible to adjust the timing on these bikes that have solid state ignitions: No points. I still don't know whether it's possible and ? if so ? how to do it.
              As for valve adjustment: So that does come first: I'll give it a shot.
              Any other brainstorms, let me know.
              J. Daniel

              Comment

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