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  • #16
    Are you sure they're XS/XJ carbs? POs have been known to swap carb racks from non-XS/XJ bikes onto these, in which case any jetting recommendations you might get can be way off...
    Fast, Cheap, Reliable... Pick any two

    '78E original owner - resto project
    '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
    '82 XJ rebuild project
    '80SG restified, red SOLD
    '79F parts...
    '81H more parts...

    Other current bikes:
    '93 XL1200 Anniversary Sportster 85RWHP
    '86 XL883/1200 Chopper
    '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
    Cage: '13 Mustang GT/CS with a few 'custom' touches
    Yep, can't leave nuthin' alone...

    Comment


    • #17
      Yeah, they are mikunis and the right number. Its just that the guts i pulled out were not SG stock, they seemed closer to XJ stock. But not the right pilots for either SG or XJ. The cable choke and 112.5's make me suspicious its maxim carbs, but i need some way to verify tht for sure. And if they are, will they work at all with the SG stock guts i put in?
      1980 XS1100 SG Stock

      Comment


      • #18
        Try looking here: http://www.xs11.com/forum/showthread...811#post363811 ... for positive ID if they're XS/XJ carbs. If any details don't match, then they're not Yamaha carbs.

        There's lots of Mikunis that were used on other bikes... there's this thread:
        http://www.xs11.com/forum/showthread.php?t=35994
        Fast, Cheap, Reliable... Pick any two

        '78E original owner - resto project
        '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
        '82 XJ rebuild project
        '80SG restified, red SOLD
        '79F parts...
        '81H more parts...

        Other current bikes:
        '93 XL1200 Anniversary Sportster 85RWHP
        '86 XL883/1200 Chopper
        '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
        Cage: '13 Mustang GT/CS with a few 'custom' touches
        Yep, can't leave nuthin' alone...

        Comment


        • #19
          Ill have to take a real close look and compare when i get off work. I'm 99%sure they are the right mikunis though. Thanks Steve.
          1980 XS1100 SG Stock

          Comment


          • #20
            Also give us some close up detail pics, we can help.
            Nathan
            KD9ARL

            μολὼν λαβέ

            1978 XS1100E
            K&N Filter
            #45 pilot Jet, #137.5 Main Jet
            OEM Exhaust
            ATK Fork Brace
            LED Dash lights
            Ammeter, Oil Pressure, Oil Temp, and Volt Meters

            Green Monster Coils
            SS Brake Lines
            Vision 550 Auto Tensioner

            In any moment of decision the best thing you can do is the right thing, the next best thing is the wrong thing, and the worst thing you can do is nothing.

            Theodore Roosevelt

            Comment


            • #21
              Alright fellas. After another inspection i have indeed found the carbs to be for the 80-82 XS and XJ. I do have a cable operated choke, without the cable. I've been told this was stock on XJs, not SGs. Can anyone back that up? After much more tinkering, i got it started. Now i just gotta get it to stay running for more than five minutes. I have full faith that i can make it run with the carbs that are on it, but out of sheer curiosity i wanna know if they were XJ carbs that i de-jetted or if it was just sloppy jetting by a PO. They are mikuni bodies for 80-82 XS/XJ like i said. The mains i pulled out were all 112.5. The pilots were non-air bleed 60s. It has a cable-op choke. There is no cross-drilled hole from the pilot to main tower. Anything else yall need to know to get a positive ID on these oddly jetted things? Keep in mind that it ran perfectly with those jets. the only problem was that i ran out of powerband at 5500.
              1980 XS1100 SG Stock

              Comment


              • #22
                I would post pictures by the way, but we're in the process of moving. So im pretty technologically limited at the moment with everything packed away. Also, i dont feel like opening the carbs again nor do i think i need to at this point. Just further tuning.
                1980 XS1100 SG Stock

                Comment


                • #23
                  Yes, the cable operated choke was only fitted to the XJ....
                  Fast, Cheap, Reliable... Pick any two

                  '78E original owner - resto project
                  '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
                  '82 XJ rebuild project
                  '80SG restified, red SOLD
                  '79F parts...
                  '81H more parts...

                  Other current bikes:
                  '93 XL1200 Anniversary Sportster 85RWHP
                  '86 XL883/1200 Chopper
                  '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
                  Cage: '13 Mustang GT/CS with a few 'custom' touches
                  Yep, can't leave nuthin' alone...

                  Comment


                  • #24
                    In that case, was the needle and emulsion tube different on the XJ? And if so, then should I assume i have the XJ needle and tube and jet accordingly? Or will it run the way i have it jetted now? (110/112.5/112.5/110 and air-bleed 42.5 pilots?)
                    1980 XS1100 SG Stock

                    Comment


                    • #25
                      Originally posted by Aaron View Post
                      In that case, was the needle and emulsion tube different on the XJ? And if so, then should I assume i have the XJ needle and tube and jet accordingly? Or will it run the way i have it jetted now? (110/112.5/112.5/110 and air-bleed 42.5 pilots?)
                      The emulsion tube I can't say as the manual isn't specific on those. But all the other jetting is different; 112.5 mains, 47.5 pilots, and 5GLZ-34 Jet needles. Generally, jetting follows the carb, not the bike, so that may be at least part of your problem.
                      Fast, Cheap, Reliable... Pick any two

                      '78E original owner - resto project
                      '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
                      '82 XJ rebuild project
                      '80SG restified, red SOLD
                      '79F parts...
                      '81H more parts...

                      Other current bikes:
                      '93 XL1200 Anniversary Sportster 85RWHP
                      '86 XL883/1200 Chopper
                      '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
                      Cage: '13 Mustang GT/CS with a few 'custom' touches
                      Yep, can't leave nuthin' alone...

                      Comment


                      • #26
                        Hmmm. I may have to yank the stuff out of these again and see if gerogefix will trade me for XJ stuff then. Sure wish i knew the number on those needles in there now.
                        1980 XS1100 SG Stock

                        Comment


                        • #27
                          You will probably find the needles to be stock. I am not sure you can find those naymore anyway, I know I have yet to source the needles for the 81 carbs.
                          Life is what happens while your planning everything else!

                          When your work speaks for itself, don't interrupt.

                          81 XS1100 Special - Humpty Dumpty
                          80 XS1100 Special - Project Resurrection


                          Previously owned
                          93 GSX600F
                          80 XS1100 Special - Ruby
                          81 XS1100 Special
                          81 CB750 C
                          80 CB750 C
                          78 XS750

                          Comment


                          • #28
                            Ill check the numbers on those needles when i pull em off again. Soon as i can get a chance too that is. If they are XJ needles i think im gonna jet up to XJ stock. Were the XJ carbs an improvement over the SG setup performance wise? And will the XJ setup work on my otherwise stock SG?
                            1980 XS1100 SG Stock

                            Comment


                            • #29
                              Originally posted by Aaron View Post
                              ....Were the XJ carbs an improvement over the SG setup performance wise? And will the XJ setup work on my otherwise stock SG?
                              Improvement? I doubt it; pretty much all the carb/timing changes Yamaha made after the '78 model were emission-related in one way or another. I don't think you'll take a hit, but don't look for again either. The XJ carbs if properly tuned should work fine on your SG; they're basically the same carb, just calibrated a bit different...
                              Fast, Cheap, Reliable... Pick any two

                              '78E original owner - resto project
                              '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
                              '82 XJ rebuild project
                              '80SG restified, red SOLD
                              '79F parts...
                              '81H more parts...

                              Other current bikes:
                              '93 XL1200 Anniversary Sportster 85RWHP
                              '86 XL883/1200 Chopper
                              '82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
                              Cage: '13 Mustang GT/CS with a few 'custom' touches
                              Yep, can't leave nuthin' alone...

                              Comment


                              • #30
                                I still would like to see pics to see if they really are XJ carbs.
                                Nathan
                                KD9ARL

                                μολὼν λαβέ

                                1978 XS1100E
                                K&N Filter
                                #45 pilot Jet, #137.5 Main Jet
                                OEM Exhaust
                                ATK Fork Brace
                                LED Dash lights
                                Ammeter, Oil Pressure, Oil Temp, and Volt Meters

                                Green Monster Coils
                                SS Brake Lines
                                Vision 550 Auto Tensioner

                                In any moment of decision the best thing you can do is the right thing, the next best thing is the wrong thing, and the worst thing you can do is nothing.

                                Theodore Roosevelt

                                Comment

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