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    #16
    Originally posted by chef1366 View Post
    I am torn between the cam chain and the igniter.
    If a cam chain was that worn it would retard the cams, if anything that should be better for high RPM, should move the powerband up...
    I agree there would be all kinds of noise before any issues with how it runs.

    Valve springs going soft, could let the valves float, but that is a LONG way below the redline RPM. I think it would take years for this problem to progress as far as not running correctly down at 6,000 RPM.

    Never seen springs cause this, have ridden some GSes with a ton of miles and years on them. Could be possible I guess. Especially if the engine has gotten really hot, enough to weaken the springs more than most?
    In cars, valves floating has a distinct feel to it, kind of a fluttering sort of thing, like every power stroke its at a different throttle position.

    So exactly what happens at 6,000?
    Is it just like hitting a rev limiter at 6,000?
    Does it start misfiring?
    Switch off like a kill switch?
    Just get less powerful as if you closed the throttle?
    Does it happen at partial throttle as well as wide open?
    Is it the same in any gear?
    Up or down hill?
    If you hold it in this RPM of the problem, then do a plug chop, what do you see?

    Is the fuel flow adequate?
    http://img.photobucket.com/albums/v5...tatesMap-1.jpg

    Life is too short to ride an L.

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      #17
      Originally posted by salty_monk View Post
      Ed,

      All the timing marks line up & there are 20 pins between the marks, it's not a tooth off.

      Dan
      the test i was referring to calls for a measurement between those 20 pins (can do it on 10 pins as well) and tells you if the camchain is stretched beyond acceptable or not
      GS850GT

      Comment


        #18
        Originally posted by tkent02 View Post
        If a cam chain was that worn it would retard the cams, if anything that should be better for high RPM, should move the powerband up...
        I agree there would be all kinds of noise before any issues with how it runs.

        Valve springs going soft, could let the valves float, but that is a LONG way below the redline RPM. I think it would take years for this problem to progress as far as not running correctly down at 6,000 RPM.

        Never seen springs cause this, have ridden some GSes with a ton of miles and years on them. Could be possible I guess. Especially if the engine has gotten really hot, enough to weaken the springs more than most?
        In cars, valves floating has a distinct feel to it, kind of a fluttering sort of thing, like every power stroke its at a different throttle position.

        So exactly what happens at 6,000?
        Is it just like hitting a rev limiter at 6,000?
        Does it start misfiring?
        Switch off like a kill switch?
        Just get less powerful as if you closed the throttle?
        Does it happen at partial throttle as well as wide open?
        Is it the same in any gear?
        Up or down hill?
        If you hold it in this RPM of the problem, then do a plug chop, what do you see?

        Is the fuel flow adequate?
        Not fuel related. Did the dance.
        It is almost like a rev limiter. Just doesn't want to climb over 6-7. Fine till that point even at wot. Reminds me of a governor I had on a moped when I was a kid.
        If a bad cam chain would move the powerband up I'm leaning towards a bad igniter but the chain was worn. LOTS of back and forth play.
        1983 GS 1100E w/ 1230 kit, .340 lift Web Cams, Ape heavy duty valve springs, 83 1100 head with 1.5mm oversized SS intake valves, 1150 crank, Vance and Hines 1150 SuperHub, Star Racing high volume oil pump gears, 36mm carebs Dynojet stage 3 jet kit, Posplayr's SSPB, Progressive rear shocks and fork springs, Dyna 2000, Dynatek green coils and Vance & Hines 4-1 exhaust.
        1985 GS1150ES stock with 85 Red E bodywork.

        Comment


          #19
          i imagine you would have thought of this but just in case ...

          automatic cam chain tensioners can get stuck and cause a loose camchain, it pays to have the tensioner checked, cleaned, lubricated
          GS850GT

          Comment


            #20
            Originally posted by psyguy View Post
            i imagine you would have thought of this but just in case ...

            automatic cam chain tensioners can get stuck and cause a loose camchain, it pays to have the tensioner checked, cleaned, lubricated
            I pulled it off and checked it out. It's OK.
            1983 GS 1100E w/ 1230 kit, .340 lift Web Cams, Ape heavy duty valve springs, 83 1100 head with 1.5mm oversized SS intake valves, 1150 crank, Vance and Hines 1150 SuperHub, Star Racing high volume oil pump gears, 36mm carebs Dynojet stage 3 jet kit, Posplayr's SSPB, Progressive rear shocks and fork springs, Dyna 2000, Dynatek green coils and Vance & Hines 4-1 exhaust.
            1985 GS1150ES stock with 85 Red E bodywork.

            Comment


              #21
              Originally posted by chef1366 View Post
              I pulled it off and checked it out. It's OK.
              i thought as much, chef, but you never know when you have a problem it's sometimes easy to overlook something simple
              good luck troubleshooting [-o<, i'm watching the thread with interest
              GS850GT

              Comment


                #22
                Today it was doing the same thing but not at 6,000rpm, much earlier in the rev range & pretty much at all throttle positions.
                Better in high gear than low gear....

                Dan
                1980 GS1000G - Sold
                1978 GS1000E - Finished!
                1980 GS550E - Fixed & given to a friend
                1983 GS750ES Special - Sold
                2009 KLR 650 - Sold - gone to TX!
                1982 GS1100G - Rebuilt and finished. - Sold
                2009 TE610 - Dual Sporting around dreaming of Dakar..... - FOR SALE!

                www.parasiticsanalytics.com

                TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

                Comment


                  #23
                  Originally posted by chef1366 View Post
                  Not fuel related. Did the dance.
                  It is almost like a rev limiter. Just doesn't want to climb over 6-7. Fine till that point even at wot. Reminds me of a governor I had on a moped when I was a kid.
                  If a bad cam chain would move the powerband up I'm leaning towards a bad igniter but the chain was worn. LOTS of back and forth play.
                  It won't be the stretched cam chain or weak valve springs causing these symptoms. Stock springs last forever with stock cam lifts. I'm still running the original springs in my 850.
                  When the motor peaks out at 7000rpm, does it miss or completely die. If it dies, try backing off the throttle until it runs normally and then snap the throttle open again and see if it pulls cleanly up to the same rpm. If it does, you can rule out fuel starvation. If not, you need to recheck the fuel supply, to and through the carbs.
                  If it's acting like a governor, there won't be much missing, just a sudden power drop, and refusal to rev higher.
                  :) The road to hell is paved with good intentions......................................

                  GS 850GN JE 894 10.5-1 pistons, Barnett Clutch, C-W 4-1, B-B MPD Ignition, Progressive suspension, Sport Demons. Sold
                  GS 850GT JE 1023 11-1 pistons. Sold
                  GS1150ES3 stock, V&H 4-1. Sold
                  GS1100GD, future resto project. Sold

                  http://i155.photobucket.com/albums/s...s/P1000001.jpg
                  http://i155.photobucket.com/albums/s...s/P1000581.jpg

                  Comment


                    #24
                    Originally posted by salty_monk View Post
                    Today it was doing the same thing but not at 6,000rpm, much earlier in the rev range & pretty much at all throttle positions.
                    Better in high gear than low gear....

                    Dan
                    I bet at this point with a weak spark your plugs are fouled.
                    1983 GS 1100E w/ 1230 kit, .340 lift Web Cams, Ape heavy duty valve springs, 83 1100 head with 1.5mm oversized SS intake valves, 1150 crank, Vance and Hines 1150 SuperHub, Star Racing high volume oil pump gears, 36mm carebs Dynojet stage 3 jet kit, Posplayr's SSPB, Progressive rear shocks and fork springs, Dyna 2000, Dynatek green coils and Vance & Hines 4-1 exhaust.
                    1985 GS1150ES stock with 85 Red E bodywork.

                    Comment


                      #25
                      Could be.... I just thought about the test we did on the coils... No volts at either connection pointd with the ignition on to either coil terminal...

                      Anyone know if that's normal or should there be a permanent live 12v to them with the ignition on?

                      Cheers,

                      Dan
                      1980 GS1000G - Sold
                      1978 GS1000E - Finished!
                      1980 GS550E - Fixed & given to a friend
                      1983 GS750ES Special - Sold
                      2009 KLR 650 - Sold - gone to TX!
                      1982 GS1100G - Rebuilt and finished. - Sold
                      2009 TE610 - Dual Sporting around dreaming of Dakar..... - FOR SALE!

                      www.parasiticsanalytics.com

                      TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

                      Comment


                        #26
                        Switched out his old carbs with my old 34s. Switched out the jets. Still the same issue. Even cut his new fuel line shorter so no hills to climb.
                        If you let off the throttle till it runs good and hit it hard it does climb to that same rpm.
                        He does have the original petcock but he said it flows good.
                        1983 GS 1100E w/ 1230 kit, .340 lift Web Cams, Ape heavy duty valve springs, 83 1100 head with 1.5mm oversized SS intake valves, 1150 crank, Vance and Hines 1150 SuperHub, Star Racing high volume oil pump gears, 36mm carebs Dynojet stage 3 jet kit, Posplayr's SSPB, Progressive rear shocks and fork springs, Dyna 2000, Dynatek green coils and Vance & Hines 4-1 exhaust.
                        1985 GS1150ES stock with 85 Red E bodywork.

                        Comment


                          #27
                          hehe we tested it when you left it switched on prime remember no way it can be drinking at that rate!
                          1980 GS1000G - Sold
                          1978 GS1000E - Finished!
                          1980 GS550E - Fixed & given to a friend
                          1983 GS750ES Special - Sold
                          2009 KLR 650 - Sold - gone to TX!
                          1982 GS1100G - Rebuilt and finished. - Sold
                          2009 TE610 - Dual Sporting around dreaming of Dakar..... - FOR SALE!

                          www.parasiticsanalytics.com

                          TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

                          Comment


                            #28
                            Originally posted by salty_monk View Post
                            Could be.... I just thought about the test we did on the coils... No volts at either connection pointd with the ignition on to either coil terminal...

                            Anyone know if that's normal or should there be a permanent live 12v to them with the ignition on?

                            Cheers,

                            Dan
                            kill switch "on", there should be permanent live at the coils (there is on mine anyway)
                            GS850GT

                            Comment


                              #29
                              Originally posted by 49er View Post
                              Stock springs last forever with stock cam lifts. I'm still running the original springs in my 850.
                              hi 49er

                              not sure how long "forever" is, but mine were shot at less than 90k kms
                              i would think the wear would also depend on how hard you push them

                              however, in this case it doesnt seem to be the issue
                              cheers
                              GS850GT

                              Comment


                                #30
                                uh... kill may well have been off, it was late by that time. I can double check that easy enough though.

                                I have Dyna Suppression wires fitted to dyna greens, stock igniter & NGK B8ES plugs from Z1.

                                Maybe it is the igniter...

                                Dan
                                1980 GS1000G - Sold
                                1978 GS1000E - Finished!
                                1980 GS550E - Fixed & given to a friend
                                1983 GS750ES Special - Sold
                                2009 KLR 650 - Sold - gone to TX!
                                1982 GS1100G - Rebuilt and finished. - Sold
                                2009 TE610 - Dual Sporting around dreaming of Dakar..... - FOR SALE!

                                www.parasiticsanalytics.com

                                TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

                                Comment

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