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    High RPM

    Hello! A few days ago my girlfriend dropped my '78 GS750 and although nothing seems to be wrong with it, the bike has been getting higher RPMs when riding at speed. When idling there's no difference, just higher RPMs when riding. I'm still pretty new when it comes to maintenance and diagnosing problems. Can anyone help me out? Thank you!

    #2
    Intake air leak? What you're describing sounds like a change of gearing (larger rear or smaller front sprocket), so a more detailed description is in order.

    Count your lucky stars that the woman walked away.
    1982 GS1100E V&H "SS" exhaust, APE pods, 1150 oil cooler, 140 speedo, 99.3 rear wheel HP, black engine, '83 red

    2016 XL883L sigpic Two-tone blue and white. Almost 42 hp! Status: destroyed, now owned by the insurance company. The hole in my memory starts an hour before the accident and ends 24 hours after.

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      #3
      Thanks for the fast response! My dad said to check the air filter so I'm planning on doing that. Just to clarify, I was trying to teach her on my bike(def gonna start out on a much slower and lighter bike now lol) so she was only going about 5 mph max when it fell on the right side.

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        #4
        I'm confused about what you are saying. Do you mean, before it ran 4,000 @ 60mph. & since the drop, it now runs 4500 rpm @ 60mph? Or when riding at 60mph, the rpm & speed just increases without giving more throttle? Also start a beginner on a smaller bike, nothing against women, but for sure start a female on something smaller. Duhhh.
        Last edited by rphillips; 01-23-2020, 05:33 PM. Reason: added info
        1983 GS1100E, 1983 CB1100F, 1991 GSX1100G, 1996 Kaw. ZL600 Eliminator, 1999 Bandit 1200S, 2005 Bandit 1200S, 2000 Kaw. ZRX 1100

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          #5
          Should've clarified the issue sorry. Yes, the first scenario. I would get about 3.5-4k rpm at 50mph and now I get 4rpm at 45. Not a huge difference but still noticeable.

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            #6
            Clutch cable issue causing slippage?
            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

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              #7
              Yeah the only thing that can cause that is either the clutch slipping or the rev counter being screwed up somehow... otherwise the relation of RPM is fixed.

              to diagnose the clutch, hit 2nd gear and open the throttle full and hard, if the revs climb without any speed increase as the power comes in then the clutch is slipping.

              quite common unless the springs have been replaced and I suspect trying to teach your bird involved a bunch of clutch work...

              TW200 (if she’s tall) or a shadow 125/250 type bike would be an ideal learner. Lots of those types of bikes around cheap enough.
              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/

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                #8
                Thank you so much! I'll test the clutch slippage today. If that's the issue, do you know the best way to fix it? Also thanks for the new learner bike recommendations

                Comment


                  #9
                  Welcome to TheGSR.

                  I too will suggest the clutch slippage idea.
                  Either the tip over messed up the clutch cable adjustment, or it just started to slip, due to age and use, and now you notice it after more cautious examinations.
                  If cable adjusted okay, and is still slipping: Replace the clutch fiber plates and clutch springs (stock springs not heavy duty) and you will find had been slipping more than you knew.

                  And my recommendation (and about any training expert) for training a newbie: need to work on stopping before they get going much. So work on barley going just rocking with feet still in place on the ground and stopping, barely going and then stopp, barley go and stop, so they learn clutch and stopping before get going much at all.

                  And relative to you teaching someone:
                  Let us ask you...... when going down road and want bike to turn, say, left, what do you do to turn bike to left??
                  Last edited by Redman; 01-24-2020, 01:58 PM.
                  http://webpages.charter.net/ddvrnr/GS850_1100_Emblems.jpg
                  Had 850G for 14 years. Now have GK since 2005.
                  GK at IndyMotoGP Suzuki Display... ... GK on GSResources Page ... ... Euro Trash Ego Machine .. ..3 mo'cykls.... update 2 mocykl


                  https://imgur.com/YTMtgq4

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                    #10
                    Originally posted by Redman View Post
                    Let us ask you...... when going down road and want bike to turn, say, left, what do you do to turn bike to left??
                    Lean left, steer right.
                    1982 GS1100E V&H "SS" exhaust, APE pods, 1150 oil cooler, 140 speedo, 99.3 rear wheel HP, black engine, '83 red

                    2016 XL883L sigpic Two-tone blue and white. Almost 42 hp! Status: destroyed, now owned by the insurance company. The hole in my memory starts an hour before the accident and ends 24 hours after.

                    Comment


                      #11
                      Since it fell on the right side, check where the clutch cable attaches down there on the right side of the engine.
                      Current Bikes:
                      2001 Yamaha FZ1 (bought same one back)

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                        #12
                        Originally posted by Rob S. View Post
                        . . . . . . . . . . . .
                        Rob, Good to see you are being sociable during your recovery.

                        But, I wasnt asking cuz I needed to know. Was asking to see what Mr CrabbyPants would say without any prompting.
                        http://webpages.charter.net/ddvrnr/GS850_1100_Emblems.jpg
                        Had 850G for 14 years. Now have GK since 2005.
                        GK at IndyMotoGP Suzuki Display... ... GK on GSResources Page ... ... Euro Trash Ego Machine .. ..3 mo'cykls.... update 2 mocykl


                        https://imgur.com/YTMtgq4

                        Comment


                          #13
                          Originally posted by Redman View Post
                          Rob, Good to see you are being sociable during your recovery.

                          But, I wasnt asking cuz I needed to know. Was asking to see what Mr CrabbyPants would say without any prompting.
                          Sorry I ruined your test. Hey, you forgot to give us homework!

                          If I don't laugh, I'll cry. And laughing is so much more subtle.
                          1982 GS1100E V&H "SS" exhaust, APE pods, 1150 oil cooler, 140 speedo, 99.3 rear wheel HP, black engine, '83 red

                          2016 XL883L sigpic Two-tone blue and white. Almost 42 hp! Status: destroyed, now owned by the insurance company. The hole in my memory starts an hour before the accident and ends 24 hours after.

                          Comment


                            #14
                            Haha yeah I do know about the lean the opposite way you want to turn. Thanks for the test
                            Originally posted by Redman View Post
                            Rob, Good to see you are being sociable during your recovery.

                            But, I wasnt asking cuz I needed to know. Was asking to see what Mr CrabbyPants would say without any prompting.

                            Comment


                              #15
                              The #1 way to train someone is to have them sign up for a riding course and you stay out of it.
                              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

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