Announcement

Collapse
No announcement yet.

Noisy Valvetrain 1978 GS550E

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Noisy Valvetrain 1978 GS550E

    I’ve been resurrecting a 1978 GS550E. It is running but has developed a knocking noise that appears to be coming from the valvetrain. I can’t tell if it is pinging from a lean condition or the valve adjustment is off now that it started.

    Here is what I’ve had to do to the motor because of rust that was in the engine.
    1. Honed cylinders
    2. installed new piston rings from Suzuki stock size.
    3. Installed a used head that machine shop verified was good with vacuum test.
    4. timed the cams and made sure the tensioner was installed correctly.

    here are some important numbers:
    compressions:
    before noise developed:
    cylinder 1 120
    cyljnder 2 125
    cylinder 3 120
    cylinder 4 130

    after noise developed:
    cylinder 1 110
    Cylinder 2 115
    Cyljnder 3 115
    Cylinder 4 125

    Valve shims and valve clearances
    cylinder 1
    intake 2-75 (.04 mm clearance)
    Exhaust 2.8 (.05 mm clearance

    cylinder 2
    intake 2-75 (.05 mm clearance)
    exhaust 2.8 (.05 mm clearance)

    cylinder 3
    intake 2.8 (.03 mm clearance)
    exhaust 2.9 (.05 mm clearance)

    cylinder 4
    intake 2.7 (.06 mm clearance)
    exhaust 2.75 (.04 mm clearance)

    im going to check the valve clearance again tomorrow but would like some guidance on if I set my clearances correctly and what I can do better.

    also, when I first started the bike after assembling it, the valvetrain was making so much of a knocking noise. It has developed the noise recently.

    any and all direction is appreciated.
    Last edited by enriquev9; 02-02-2023, 08:47 PM.

    #2
    Attaching a video.

    I was also planning on re torquing the head bolts also.
    video, sharing, camera phone, video phone, free, upload

    Comment


      #3
      1. Valve adjustment ??
      2. Cam 'walk'??
      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


        #4
        I am a little confused. The noise started after you adjusted the valves?
        A long shot but it sounds a bit like an exhaust leak. Did all the exhaust gaskets get installed?
        2@ \'78 GS1000

        Comment


          #5
          You might want to check the cam chain tensioner to make sure it's functioning properly
          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


            #6
            The compression change is likely the key. What could cause a 10 psi drop on 1 and 2 but only 5 psi on 3 and 4?
            Recheck everything.
            the only thing I think could change is timing jumped from an improperly operating tensioner or the head gasket was not properly torqued and it is leaking after heat cycling.
            1983 GS 550 LD
            2009 BMW K1300s

            Comment


              #7
              Originally posted by steve murdoch View Post
              I am a little confused. The noise started after you adjusted the valves?
              A long shot but it sounds a bit like an exhaust leak. Did all the exhaust gaskets get installed?
              this project has been on the back burner for a while. Now I’m trying to finish it. I can safely say that when I moved to Arizona and was tinkering with the bike again it wasn’t making that sound. I started the bike one day after installing the tank and went for a test ride. (I really thought I was close to being finished). But then it started making that noise out of nowhere.

              I can honestly say I adjusted the valves as I assembled the top end back together. Can’t remember how long ago that was.

              I plan to take the valve cover off and hopefully I will get some answers.

              yes. All exhaust gaskets were installed. I sprayed some WD40 on the exhaust and didn’t hear any change in idle or see bubbling.

              Is there a better way to check for exhaust leaks?

              Comment


                #8
                Originally posted by Nessism View Post
                You might want to check the cam chain tensioner to make sure it's functioning properly
                I will need to check. Do I have to take the carbs off for this?

                Comment


                  #9
                  Originally posted by Cipher View Post
                  The compression change is likely the key. What could cause a 10 psi drop on 1 and 2 but only 5 psi on 3 and 4?
                  Recheck everything.
                  the only thing I think could change is timing jumped from an improperly operating tensioner or the head gasket was not properly torqued and it is leaking after heat cycling.
                  I agree on checking the tensioner. Will have an update when I take off the valve cover.

                  I also have a feeling that I need to re torque the cylinder head bolts. I just hope I didn’t blow the gasket

                  sorry guys. This has been quite an adventure for me with his bike.

                  Comment


                    #10
                    "I’ve been resurrecting a 1978 GS550E. It is running but has developed a knocking noise that appears to be coming from the valvetrain.​"

                    I had that "knocking"/banging noise on a 2000 GS500E I had years back. I tried everything with no luck. It was bad at idle and faded as engine speed went up, completely gone @ +/- 2000 RPM. Bike ran great but embarrassing at stop lights. Even called Suzuki. Everyone said not to worry, no harm, was common issue. I gave bike away to a relative before I solved it. Not sure the "forget about it" advice was good. I would have kept chasing it but passed problem on with no guilt. Bike was stolen a few weeks after I gave it away. Nice bike but made me ride with less care than I do on my GS850G so better off without it. Good luck.
                    Rides ROADKILL-1981 GS850G, very slowly these days. :dancing:

                    Comment


                      #11
                      Update. I torqued the cylinder head to spec again. Some of the nuts were loose.

                      it’s fixed now. Way more quiet.

                      Comment


                        #12
                        To test the tensioner just gently turn the big knurled knob to the left a little. You should feel the drive rod pulsing. Also be sure it's adjusted right. Tighten the screw till it touches the drive rod then out 1/4 turn and tighten jam nut
                        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

                        Working...
                        X