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77 GS750 PO couldn't get running

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    77 GS750 PO couldn't get running

    I ran across this 77 GS750 which is in really nice shape. Clock shows about 9500 miles! Paint, trim and overall complete. I wasn't looking for another bike but when opportunity presents itself, I have to take advantage of it. PO had put in new points, condenser, plug wires and caps and battery. He also bought a pair of new tires but not installed. Only starts on ether I'm told. Fuel tank looks like new inside and out. Sorry no pics yet but I'm supposed to go pick it up tomorrow after the bank opens.

    Looks like VM26's and stock air box but the boots weren't fully installed. Bike had been sitting for some years and is dusty but paint and chrome still look good. I'm guessing the PO tried to clean the carbs himself so first order of business is to pull the rack and see what I can do to "fix" them. Rear brake is locked up but I'm sure I can work through that. I usually just pull the entire brake system apart and clean thoroughly replacing worn parts anyway.

    Any gotchas or mods that you know of I should perform?

    Also has a 630 chain but not in bad shape nor the sprockets. Is there a conversion to 530 that is well known?

    Thanks for looking.

    #2
    Adjust the valves straight away. Very likely to never have been done before.
    Ed

    To measure is to know.

    Mikuni O-ring Kits For Sale...https://www.thegsresources.com/_foru...ts#post1703182

    Top Newbie Mistakes thread...http://www.thegsresources.com/_forum...d.php?t=171846

    Carb rebuild tutorial...https://gsarchive.bwringer.com/mtsac...d_Tutorial.pdf

    KZ750E Rebuild Thread...http://www.thegsresources.com/_forum...0-Resurrection

    Comment


      #3
      Valves as was mentioned and save this place for future use. VM carb rebuild tutorial is on the right side margin. Choose the 8 valve early 750 service manual.

      MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
      1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

      NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


      I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

      Comment


        #4
        Originally posted by chuck hahn View Post
        Valves as was mentioned and save this place for future use. VM carb rebuild tutorial is on the right side margin. Choose the 8 valve early 750 service manual.

        http://members.dslextreme.com/users/bikecliff/
        thank you for reminding me of Bass Cliff's site. I have a "favorite" to his site and every time I go there, he has put up more info or so it seems. I already found and downloaded the correct GS750 service manual.

        You guys have no way of knowing but this makes the 33rd "barn find" I've owned. I don't claim to be an expert but I do get them running, safe and reliable before I flip them. Working on these old bikes is something I love to do and keeps me off the streets.... Even with that said I always appreciate your input and suggestions. I think the last time I was here I had a GS750E that had sat for 10 years in a guys back yard uncovered. You guys pointed out the oil pressure regulator mod and, as a result, I even did a pic "How to" while I did the mod for future reference. I already have the Suzuki valve shim tool and once I get the bike here I'll order the gaskets needed and shims if required.

        Comment


          #5
          Found the problem with the carbs. The fuel mixture screws on 1 and 2 are broken off inside the carb throat. These are the screws that adjust fuel mix at idle, nearest the cylinder head not the air screws by the air cleaner. I hate it when that happens. Only reason for it is to tighten them too tight. They are actually protruding into the throat! Working on getting them out now. Then I have to source two new screws.

          Comment


            #6
            Z1 has the fuel screws
            1978 GS 1000 (since new)
            1979 GS 1000 (The Fridge, superbike replica project)
            1978 GS 1000 (parts)
            1981 GS 850 (anyone want a project?)
            1981 GPZ 550 (backroad screamer)
            1970 450 Mk IIID (THUMP!)
            2007 DRz 400S
            1999 ATK 490ES
            1994 DR 350SES

            Comment


              #7
              Thank you sir. Now to get the old ones out. I think I'll pose the question in the carb forum.

              Comment


                #8
                I answered the pilot screw dilemma in your other thread.
                MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                Comment


                  #9
                  Now where to source the screws. Z1, as suggested, only has the pilot screw for 80 and up BS carbs. These are VM. A search on eBay didn't bring anything that would work. I'll keep looking.

                  Comment


                    #10


                    Page 7.

                    They are out of Canada so it takes a few more days for delivery. I get bowl gaskets from them..FOUR gaskets for like 12 bucks..adding the shipping thats still cheaper than just two from suzuki. Look around the site as they have fuel tees and such also
                    MY BIKES..1977 GS 750 B, 1978 GS 1000 C (X2)
                    1978 GS 1000 E, 1979 GS 1000 S, 1973 Yamaha TX 750, 1977 Kawasaki KZ 650B1, 1975 Honda GL1000 Goldwing, 1983 CB 650SC Nighthawk, 1972 Honda CB 350K4, 74 Honda CB550

                    NEVER SNEAK UP ON A SLEEPING DOG..NOT EVEN YOUR OWN.


                    I would rather trust my bike to a "QUACK" that KNOWS how to fix it rather than a book worm that THINKS HE KNOWS how to fix it.

                    Comment


                      #11
                      Update... Silly me I was searching for a Suzuki carb part. Seems Z1 does carry the screw but for a Kawi. I'll put two on order now..Thanks again guys

                      Comment


                        #12
                        Got the carbs put back together and installed. I had to soften the air box boots but they went on easily. Love these old GS bikes. So easy to service the carbs. I had to clean and rebuild the rear caliper. PO had already rebuilt the rear MC. Test ride went great. Runs awesome and sounds ... well "mean" when you get happy with the throttle.



                        Comment


                          #13
                          Good to hear you got the carbs sorted.
                          Curious as to the "treatment" of the front fender.
                          Is that paint flaking to reveal chrome or the other way round?
                          2@ \'78 GS1000

                          Comment


                            #14
                            Wow awesome bike...looks just like mine! Do you know what the mufflers on those are? I've seen a similar set on a GS550 and always thought they looked cool.
                            1980/1981 GS450 - GS500 Cylinder + Piston Swap - "De-L'ed", custom seat, CB350 bits, 18" rear, etc.
                            1977 GS550
                            1977 GS750 - Cross country trip thread

                            Comment


                              #15
                              Originally posted by steve murdoch View Post
                              Good to hear you got the carbs sorted.
                              Curious as to the "treatment" of the front fender.
                              Is that paint flaking to reveal chrome or the other way round?
                              Thank you.
                              The chrome has peeled off of the fender in places and it looks like the PO sprayed paint primer on it but that's falling off too. I was looking for suggestions for what to do. My idea was to lightly sand all of it to bare metal and polish it with buffer and SS compound. Or I could give it a brushed SS look with sand paper. Or I could prime and paint it but I'd never match the color on the bike so that is my last resort. I figured that if I start with sanding, using like 600 or 1000 grit, I can get a nice buff-able surface. If I screw that up then I can sand with like 600 or 400 and try for brushed SS. But I'm pretty sure I won't like the look of that. I guess I could have it re-chromed (expensive) or powder coat a shiny chrome like finish. I know a guy who does powder coat and owes me a favor. I've even toyed with painting it gloss black and the fork lowers gloss black too. Fork lowers will need to be either painted or stripped and polished. I've done a few fork lower polished and it looks good when I'm done.

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