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    fuel problems

    I reciently purchased a 78 GS1000 that sat for quite some time in their garage. The person I bought it from did not run it very often so it did not surprise me when it did not start. After removing the carbs for a major cleaning I reinstalled them with the following adjustments:1 & 1/4 turns on the air screws & 2 turns out on the screw on the bottom of the carb (forgive my lack of termonoligy).I also replaced the spark plugs & the resistor caps on the plugs. I also checked the points to ensure they had the correct gap & was surprised when I looked @ them as they appeared to be fairly new. The original air filter was also missing so I purchased four pod filters to replace the original air filter. The bike runs much better than it did when I brought it home, but it still runs rich as well as a lack of power in the mid range RPM's. The confusing thing to me is, if the pods should have leaned out the mixture, why is it still running rich & once I correct that problem, what jets do I need to switch to to compensate for the increased air flow (was told I would have to do this by my local Suzuki dealer). Oh, just to rule it out, I did an ohm check on the primary & secondary side of the coils. The primary side ohmed out within the tolerance the book gave but the secondary was over the range with the resistor caps in place but when I removed them, they were also within tolerance. I also completed an MFD check on the capacitors for the points. It also proved to be good. Any thoughts or suggestions would be much appreciated. According to the Suzuki book the seller gave to me with the bike the carbs are Mukuni VM26SS.

    #2
    No one has chimed in yet, so I'll ask a few questions. How do you know that the bike is running rich? You're lack of power in mid-range sounds like a lean condition. Also different jets and carb circuits operate at different throttle settings, so if checking lean/rich condition (I assume that's a plug check) it needs to be checked at different throttle settings, preferably while riding.

    When you cleaned your carbs did you replace the O-rings? Did you take the carbs completely apart (separate them) when you cleaned them? Has the carb been synchronized? Float settings correct?

    Also, do you know the condition of your intake manifold O-rings?

    Comment


      #3
      As far as the rich I was going on the odor of the exhaust coming out of the pipes & at times the greyish color of the exhaust as well as the color of the plugs (they are quite black with soot),however I have not done a check on them while riding. I did replace some of the O-rings when I had the carbs apart but not all of them. Also I did not seperate them when I cleaned them.I removed the bowls & all of the jets & float assembly, & soaked them with carb cleaner & blew them out w/compressed air.I also noticed one of the jets was almost completely blocked off with debris so I used a single strand of a #16 wire to clean them out. Would I be better off completely seperating them? Am I missing areas that need attention by not seperating them? I am quite mechanically inclined but when it comes to carbs, I do not have much experience with them. I performed a carb sync which seemed to help some. And to be quite frank, I didn't think of the condition of the O-rings inside of the intakes.
      Thank you for your input,It is much appreciated. Any more thoughts would be also greatly appreciated.

      Comment


        #4
        Maybe I'm misunderstanding you, but if you only cleaned the bowls and the jets themselves, there were a lot of passages in the main body of the carb that could still be gunked up. Usually if you're going to "tank" the carb it all has to come totally apart and be cleaned especially the small passages in the body of the carb, choke circuit etc. Maybe you did that and I'm misreading you.

        You're float drop needs to be very accurate so that you aren't flooding your carbs, that could be a part of the problem. Did you check that? Drop is measured from the gasket surface (no gasket) to the bottom of the float. Specs should be in your manual.

        Intake manifold boots are really a routine maintenance item, on a bike that old if they've never been changed they need to be. Other wise you'll have a vacuum leak that could cause the problems you describe. Make sure you use an OEM Ring from Suzuki, they are some sort of special material designed for that specific purpose. When you do that trade the phillips head screws for allen head screws. If you want some more info. on that there's a good website that will walk you through it.

        Re-jetting for the pods is beyond what I know about. But there are some guys on the forum who are real experts, so when you get to that point keep asking and you'll get through it.

        Don't start doing that though unless you know that your carbs are absolutely clean, float settings are accurate, intake O-rings are good. Also valve adjustment needs to be accurate as well before you start tuning your carb.

        Good luck!
        Last edited by Guest; 03-15-2006, 12:58 AM.

        Comment


          #5
          You did not read wrong. I did not "tank" the carbs. Looks like I will be pulling them back the bike to brake them down to parade rest & giving them a more complete cleaning. As far as the type of cleaner, do you have any recomendations as to any particular brand to use?

          Also as far as OEM parts I have been eyeing bikebandit.com for parts. They sell OEM parts but at a much better price than Suzuki. Do you have any input on them? I have not purchased anything from them as I am leary of doing business online.

          When I put them back together I will also recheck the float height. I'm not sure if it's that or something with my fuel cut off but I noticed yesterday that my #2 carb was overflowing with fuel at a rather decent rate.

          Again thanks for the info. It is much welcome.

          Comment


            #6
            Good advice above. Gotta clean the carbs completely taken apart. Use hi-pressure air too.
            Adjust floats to .94". I recommend Robert Barrs o-ring kit.
            Remove the two floatbowl vent lines and leave the ports open for pods.
            Side air screws should be adjusted for highest rpm. Start them at 1 3/4 turns out. Pilot fuel (underneath) should be about 1 1/4 turns for just the pods and stock pipe.
            Carbs must be bench synched followed by a vacuum tool synch.
            But first, where are the jet needle e-clips located? What position on the needles? What size pilot and main jets are in there?
            And on the seventh day,after resting from all that he had done,God went for a ride on his GS!
            Upon seeing that it was good, he went out again on his ZX14! But just a little bit faster!

            Comment


              #7
              Originally posted by louisciccoli
              Also as far as OEM parts I have been eyeing bikebandit.com for parts. They sell OEM parts but at a much better price than Suzuki. Do you have any input on them? I have not purchased anything from them as I am leary of doing business online.
              Bikebandit is great. ronayers.com is usually cheaper but you need the Suzuki part no. to place an order, they won't or can't look them up for you (good place to buy though). Get your o-rings from cycleorings.com (Robert Barr as stated above).

              Comment


                #8
                macmatic has the manifold o-rings now too. and cycleorings.com, thanks again Robert!!

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                  #9
                  Gents,
                  Thanks for all the advice. It should be a big help. I'll be taking the carbs off & back into work on Monday to give them a thorough cleaning there (it's nice to work in a shop with lots of tools for a living!).

                  Comment


                    #10
                    I had the carbs apart today & found some more debris. I also noted the sizes of the jets. The main is a 105 & the pilot is a 15. As far as the E-clips, I need to remove the needles from the throttle valve yet. It was proving to be quite stubborn so I need to figure out a better way to remove the screws that holds it together. I am also having a bit of trouble removing the #4 carbs air adjustment screw. My guess is it is from being exposed to the elements more than 2 & 3 are. #1 came out but with some difficulty. I am currently awaiting the new o-rings & bowl gaskets to come in. Didn't get home in time to call Suzuki to order the new intake o-rings. By the way, my fuel tubes do not have an actual o-ring on them , instead they are a metal tube surrounded by a rubber like material that has o-rings formed to it. Any thoughts about these? Can I reuse them or should I replace them? They have no fuel leaking from them & I don't think they draw any vacuum or am I wrong?

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