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  • Chassis diag.

    On my SG I have an issue I'm trying to diagnose and fix with the balance of the bike. Here's the thing.....

    I've always been able to set the throttle lock and take my hands off the bars on the highway and go for miles without touching them steering only with weight transfer. Since I had a little mishap last fall if I try that it rolls off to the right and no amount of weight transfer can correct it.

    When I crashed the only real damage was the broken fairing and bags and the triple tree got twisted and bent my tubular steel fork brace. When I straightened out the triple tree I checked the fork tubes with a straight edge and they don't seem to be bent and everything LOOKS fine. The bike handles and rides just as well as ever it's just that "pull" that has me baffled.

    I'm going to go ahead and take the forks off this winter and check them closer but I was just wondering if anyone else has run into this type of issue before. I could rid it forever like it is but it just irritates me that it's not EXACTLY right.
    Greg

    Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

    ― Albert Einstein

    80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

    The list changes.

  • #2
    Is there any difference in tire wear pattern since the accident?

    See if you can come up with a couple of 8' fluorescent tubes. Use them to check alignment back to front. If the triple tree was actually bent, I think you should go ahead and replace it. As you know, what's off 1/64" at the top could translate to a problem at the bottom.
    Marty (in Mississippi)
    XS1100SG
    XS650SK
    XS650SH
    XS650G
    XS6502F
    XS650E

    Comment


    • #3
      Tire wear was my first guess too. How about a spacer out of alignment, etc.? Suspension is one of those things that u bend it once, it'll never be the same as new.
      1979 XS1100F
      2H9 Mod, Truck-Lite LED Headlight, TECHNA-FIT S/S Brake Lines, Rear Air Shocks, TKAT Fork Brace, Dyna DC-I Coils, TC Fuse Block, Barnett HD Clutch Springs, Superbike Handlebars, V-Star 650 ACCT, NGK Irridium Plugs, OEM Exhaust. CNC-Cut 2nd Gear Dogs; Ported/Milled Head; Modded Airbox: 8x8 Wix Panel Filter; #137.5 Main Jet, Viper Yellow Paint, Michelin Pilot Activ F/R, Interstate AGM Battery, 14MM MC, Maier Fairing, Cree LED Fog Lights.

      Comment


      • #4
        Originally posted by jetmechmarty View Post
        Is there any difference in tire wear pattern since the accident?

        See if you can come up with a couple of 8' fluorescent tubes. Use them to check alignment back to front. If the triple tree was actually bent, I think you should go ahead and replace it. As you know, what's off 1/64" at the top could translate to a problem at the bottom.
        I haven't noticed a difference in tire wear. I still have the same front tire I had at the time. It made it's second trip to NC this year. It's cupping on the sides but my fronts tires always do due to my aggressive riding. The rear I just took off looks normal.

        As far as I can tell the triple tree isn't bent. It just twisted on it's axis. However, I do see your point. It may not have slipped, it may have twisted the neck.

        Another thing to look at.
        Last edited by BA80; 10-14-2014, 08:01 PM.
        Greg

        Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

        ― Albert Einstein

        80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

        The list changes.

        Comment


        • #5
          Did you check the wheel axle? Most of the time they bend in an accident.
          XS1100 3X0 '82 restomod, 2H9 '78 chain drive racer, 3H3 '79 customized.
          MV Agusta Brutale 910R '06.
          Triumph 1200 Speed Trophy '91, Triumph 1200 '93.
          Z1 '73 restomod, Z1A '74 yellow/green, KZ900 A4 '76 green.
          Yamaha MT-09 Tracer '15 grey.
          Kawasaki Z1300 DFI '84 modified, red.

          Comment


          • #6
            No I haven't Math. Thank you. Never considered that.
            Greg

            Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

            ― Albert Einstein

            80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

            The list changes.

            Comment


            • #7
              10 to 1 its the triple tree. That's my bet.
              Mike Giroir
              79 XS-1100 Special

              Once you un-can a can of worms, the only way to re-can them is with a bigger can.

              Comment


              • #8
                Had a Yamaha Radian after my SF, made a turn onto the freeway ramp and the rear went out, lightly touched down, spun around a couple times, stopping right on the slab. Jumped up checked myself, then the bike, scrape on the brake lever end, mirror and cap on the throttle grip. I got back on and continued 25 mi. trip to work setting off 4th of July fire works, no problem. Many days later I noticed if I lifted my hands off the grips it would start to wobble and slowly turn into a tank slapper, if I grabbed hold again I could calm it back down instantly. Took it to the dealer they checked it out and put a new tire on. I picked it up and checked it out, same thing. Brought it right back, they sent one of the techs out on it, he came back and said yes it does wobble into a tank slapper. They gave me some money back, basically charging me just for the tire and said that's the way it is ? I traded it at another dealer on a BMW K100LT, this tech must never have lifted his hands from the grips ? Something amiss but never found out what ?
                76 XS650 C ROADSTER
                80 XS650 G Special II
                https://ibb.co/album/icbGgF
                80 XS 1100 SG
                81 XS 1100LH/SH DARKHORSE
                https://tinyurl.com/k6nzvtw
                AKA; Don'e, UD, Unca Don'e

                Comment


                • #9
                  Hey Greg,

                  Aside from either bending the TT, you may have also tweaked the steering neck/frame, just a degree or 2, but enough to throw it out of true balance!? The front wheel will be a little out of line with the rear, so like someone stated, either a pair of fluorescent tubes to see if the rear is in line with the front....or a laser level, or just rolling it across a hard surface that has a thin layer of sand over it and then inspect your tire tracks to see if they are inline or if you can see the rear off position from the front?? Hope it's the TT and not the frame neck!

                  T.C.
                  T. C. Gresham
                  81SH "Godzilla" . . .1179cc super-rat.
                  79SF "The Teacher" . . .basket case!
                  History shows again and again,
                  How nature points out the folly of men!

                  Comment


                  • #10
                    I thought of that too TC but I don't think that it was that much of force.

                    If you look at this pic that Tod took you can see a big plowed spot, right where whoever that is left leg is, where the front wheel grabbed on to the left bank of the ditch and tried to tear the bars out of my hands. I'm pretty sure that's where the forks got tweaked.



                    The bars were off to the right and the wheel to the left when the dust settled. Basically it was that force and me fighting back that did it.
                    Greg

                    Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

                    ― Albert Einstein

                    80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

                    The list changes.

                    Comment


                    • #11
                      You probably tried this when you examined your forks, but do you see any slight turning of the wheel when you compress and pull up the forks. The bend or kink in the tube could be concealed.
                      Skids (Sid Hansen)

                      Down to one 1978 E. Stock air box with K&N filter, 81H pipes and carbs, 8500 feet elevation.

                      Comment


                      • #12
                        No I haven't skids. But like I said, I'll be removing the forks this winter to examine them better. I need to put a little heavier oil in them anyway.

                        I'll disassemble the triple tree then too. Haven't touched it in about 5 years.
                        Greg

                        Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

                        ― Albert Einstein

                        80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

                        The list changes.

                        Comment


                        • #13
                          The quickest way I've found to check the fork alignment is to get a small sheet of glass and lay it across the fork tubes above the lowers. That'll tell you in a second if they're twisted if the glass can wobble. If it sits flat against both tubes, they should be ok.
                          79 SF Special W/ Stock all original motor @ 384,000klms
                          Stock exhaust, stock airbox, XJ sump, 78E carbs, Xs1100RH seat, Bosch superhorns, 5/8ths front M/c, braided lines, sintered SBS pads, drilled discs, progressive springs, 8" 50w HID headlight 4300K, 2 x 50w HID spiral driving lights, KONI shocks, Spade fuse box
                          *Touring mode - Plexistar 2 screen, Gearsack rack & bag & saddlebags, homebuilt towbar
                          *"The Keg"- UC torana hubs, XS11 discs, Tokico 4 spot calipers

                          Comment


                          • #14
                            Originally posted by Eveready1100 View Post
                            The quickest way I've found to check the fork alignment is to get a small sheet of glass and lay it across the fork tubes above the lowers. That'll tell you in a second if they're twisted if the glass can wobble. If it sits flat against both tubes, they should be ok.
                            That's actually how I did it when I straightened them up. Not glass but with a good flat piece of wood.
                            Greg

                            Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

                            ― Albert Einstein

                            80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

                            The list changes.

                            Comment


                            • #15
                              How flat can a piece of wood be? I'm sure you can understand how that sounds.

                              When you get those forks all apart, that might be a good time to upgrade. You mentioned you had cupping in the front tire. I don't. Ya know what I mean, Vern?
                              Marty (in Mississippi)
                              XS1100SG
                              XS650SK
                              XS650SH
                              XS650G
                              XS6502F
                              XS650E

                              Comment

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