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    Scratches inside cylinder head

    Hello all. I've got the top end of my 1979 GS850 apart right now. I noticed yesterday that just above where #2 intake valve and springs sits there's some scratches in the cylinder head casing. I didn't really know what to think about it, other than, someone else, at some point, has taken this top end apart. The PO is a friend of mine and he says he hadn't opened up the engine at all, so had to be someone prior to him. I don't think this had any negative impact on how the bike ran, but I wanted to see what you all had to say about it.

    Ryan

    1979 GS850G - currently undergoing a major overhaul
    1986 GSX-R750 - I'm figuring it out

    #2
    From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.
    ‘83 GS850G
    ‘12 R1200RT

    Comment


      #3
      Originally posted by mehall2 View Post
      From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.
      Or had a valve spring compressor slip.

      Comment


        #4
        Just smooth down the raised metal. Hopefully the valve guide is in good shape.

        Mad
        83 GS750E
        2006 ZX14
        2004 KTM 450 EXC
        2001 Yamaha Big Bear

        Comment


          #5
          I would be more worried about that cam journal surface.
          1981 GS850G "Blue Magic" (Bike Of The Month April 2009)

          1981 GS1000G "Leo" (Bike Of The Month August 2023)

          Comment


            #6
            Originally posted by mehall2 View Post
            From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.
            Something like that, yeah. I'm having trouble picturing exactly what they were trying to do, but the mind of the PO is a terrible, strange place I do not understand. But that sure looks like human error. Maybe some weird accident with a homemade valve spring compressor. Maybe they shattered a shim trying to get it out with a screwdriver or something, and a piece bounced around in there.



            Originally posted by 2BRacing View Post
            I would be more worried about that cam journal surface.
            Same. Are the other journals OK? What does the cap on that journal look like? What does that surface on the camshaft look like?

            The damage around the valve bucket well is pretty much irrelevant.
            1983 GS850G, Cosmos Blue.
            2005 KLR685, Aztec Pink - Turd II.3, the ReReReTurdening
            2015 Yamaha FJ-09, Magma Red Power Corrupts...
            Eat more venison.

            Please provide details. The GSR Hive Mind is nearly omniscient, but not yet clairvoyant.

            Celeriter equita, converteque saepe.

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            Comment


              #7
              If the cam journal shown checks out as far as wear, except for that damage, and the cap is ok, then that would work fine. Check the clearance.
              NO PIC THANKS TO FOTO BUCKET FOR BEING RIDICULOUS

              Current Rides: 1980 Suzuki GS1000ET, 2009 Yamaha FZ1, 1983 Honda CB1100F, 2006 H-D Fatboy
              Previous Rides: 1972 Yamaha DS7, 1977 Yamaha RD400D, '79 RD400F Daytona Special, '82 RD350LC, 1980 Suzuki GS1000E (sold that one), 1982 Honda CB900F, 1984 Kawasaki GPZ900R

              Comment


                #8
                Originally posted by Maddevill View Post
                Just smooth down the raised metal. Hopefully the valve guide is in good shape.

                Mad
                Yeah, the guide seems to be in good shape.
                Ryan

                1979 GS850G - currently undergoing a major overhaul
                1986 GSX-R750 - I'm figuring it out

                Comment


                  #9
                  Originally posted by bwringer View Post
                  Are the other journals OK? What does the cap on that journal look like? What does that surface on the camshaft look like?

                  The damage around the valve bucket well is pretty much irrelevant.
                  Here's pics of each journal, and the cap in question. They all look fine to me but you guys would know better.













                  Ryan

                  1979 GS850G - currently undergoing a major overhaul
                  1986 GSX-R750 - I'm figuring it out

                  Comment


                    #10
                    Originally posted by 1980GS1000E View Post
                    If the cam journal shown checks out as far as wear, except for that damage, and the cap is ok, then that would work fine. Check the clearance.
                    Thank you 1980GS1000E. The engine ran pretty well prior to disassembling, so I'm under the impression the scratches were of no significance but, of course, I wanted to get a consensus from the group.
                    Ryan

                    1979 GS850G - currently undergoing a major overhaul
                    1986 GSX-R750 - I'm figuring it out

                    Comment


                      #11
                      Oofah. Some scoring on the cam journals. If you can feel the scratches with a fingernail, you have problems. If you can't, just buff them a little by hand with a Scotchbrite pad.

                      Mad
                      83 GS750E
                      2006 ZX14
                      2004 KTM 450 EXC
                      2001 Yamaha Big Bear

                      Comment


                        #12
                        Originally posted by Maddevill View Post
                        Oofah. Some scoring on the cam journals. If you can feel the scratches with a fingernail, you have problems.
                        Thanks Mad. Just went over all of the journals with a fingernail, smooth as a babies bottom. It's my understanding that there's gonna be some scoring, and that this amount is completely normal.

                        Originally posted by Maddevill View Post
                        If you can't, just buff them a little by hand with a Scotchbrite pad.
                        With respect, wouldn't a Scotch-Brite pad scratch up the surface?
                        Last edited by RustyTank; 01-24-2021, 07:58 PM.
                        Ryan

                        1979 GS850G - currently undergoing a major overhaul
                        1986 GSX-R750 - I'm figuring it out

                        Comment


                          #13
                          Originally posted by bwringer View Post
                          What does that surface on the camshaft look like?
                          I checked out the camshaft, it looked fine, no dings or obvious scratches.
                          Last edited by RustyTank; 01-24-2021, 06:40 PM.
                          Ryan

                          1979 GS850G - currently undergoing a major overhaul
                          1986 GSX-R750 - I'm figuring it out

                          Comment

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