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    Valve clearance

    Sorry guys for asking so many questions... but I'm trying to do many things on the bike at the same time.

    I took the clearance today (first time ever) with my new gauge that only goes down to .04mm. Here they are

    Cam Position (A: cam vertical B: cam horizontal)

    Intake Exhaust:
    Cylinder:

    1) A: .04mm (gauge did not fit) B: .04mm (gauge did fit)

    2) A: .05mm B: .04 (did fit)

    3) A: .06mm B: .06mm

    4) A: .06mm B: .04mm

    Exhaust:

    1) A: .06mm B: .06mm

    2) A: .11mm B: .11mm

    3) A: .11mm B: .10mm

    4) A: .04 (gauge did not fit) B: .04 (gauge did not fit)


    So now what? I don't have any more $ left (got nailed unexpectedly at the DMV for $180 )

    Can I switch the shims from cylinder 1 (intake) with 2 (exhaust) and 3 (exhaust) with 4 (exhaust) or do I have to get new/used shims? (cycle recycle II right?)

    Thanks again!

    #2
    Yes, you can switch shims around. Thats how its usually done. :-)
    Just write down which shim came from where and what the clearance was
    with the original shim.

    Earl

    Originally posted by bexabarr
    Sorry guys for asking so many questions... but I'm trying to do many things on the bike at the same time.

    I took the clearance today (first time ever) with my new gauge that only goes down to .04mm. Here they are

    Cam Position (A: cam vertical B: cam horizontal)

    Intake Exhaust:
    Cylinder:

    1) A: .04mm (gauge did not fit) B: .04mm (gauge did fit)

    2) A: .05mm B: .04 (did fit)

    3) A: .06mm B: .06mm

    4) A: .06mm B: .04mm

    Exhaust:

    1) A: .06mm B: .06mm

    2) A: .11mm B: .11mm

    3) A: .11mm B: .10mm

    4) A: .04 (gauge did not fit) B: .04 (gauge did not fit)


    So now what? I don't have any more $ left (got nailed unexpectedly at the DMV for $180 )

    Can I switch the shims from cylinder 1 (intake) with 2 (exhaust) and 3 (exhaust) with 4 (exhaust) or do I have to get new/used shims? (cycle recycle II right?)

    Thanks again!
    Komorebi-The light filtering through the trees.

    I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

    Comment


      #3
      Originally posted by bexabarr
      Can I switch the shims from cylinder 1 (intake) with 2 (exhaust) and 3 (exhaust) with 4 (exhaust) or do I have to get new/used shims? (cycle recycle II right?)
      but does this switch make sense. I'm still trying to figure all this stuff out.

      Comment


        #4
        Only if its the thickness you need on that valve. Youre going to have to by some, but with any luck, you will already have some of the sizes you need.

        Earl

        Originally posted by bexabarr
        but does this switch make sense. I'm still trying to figure all this stuff out.
        Komorebi-The light filtering through the trees.

        I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

        Comment


          #5
          Myself, I would buy the needed shims to get the .11mm clearance down to .06mm. That way you have a couple of extra shims to work with.

          For the clearances of < .04mm, I would do one of two things:
          1. Find a .03mm thickness guage to determine if they are actually out of spec.
          2. Just use the next thinner shim. Maybe you'll get lucky and the .11mm clearance shim is just what you need.

          Comment


            #6
            It really helps to have a feeler gauge that goes down to .03mm - they are expensive, but it makes the process much easier.

            Secondly, as you've seen, you can get different measurement in each of the 'proper' cam lobe positions. I think you're better off if you follow the procedure in the manual exactly. Even though it should be the same with the lobe in either position, it doesn't always seem to be the case. If you use the approved procedure consistently, you can't go wrong and it's easier to figure out what to do when you have one consistent measurement per valve. On my '78 750 and the '82 850, the procedure is:

            ----------------------------------
            turn crank until
            #1 exhaust cam lobe pointing forward parallel with the top of the head
            - check #1 exhaust
            - check #2 exhaust

            rotate crank 180 degrees
            #1 intake cam lobe pointing up perpendicular to the top of the head
            - check #1 intake
            - check #2 intake

            rotate crank 180 degrees
            #4 exhaust cam lobe pointing forward parallel to the top of the head
            - check #3 exhaust
            - check #4 exhaust

            rotate crank 180 degrees
            #4 intake came lobe pointing up perpendicular to the top of the head
            - check #3 intake
            - check #4 intake

            Once you have your existing measurements, if the clearance for a valve is too big, put in the next larger shim - they come in .05mm increments. So, if you have a 2.60 shim and are getting a clearance of .11mm, putting in a 2.65 shim brings it to .06mm which is within tolerance. Same the other way. If the .04mm feeler doesn't fit, put in the next smaller shim. If that puts it up to .08, then it must have been at .03 and is in tolerance either way.

            As Earl said, you'll probably have to buy a few shims, but once you get all your measurements, you can see which ones you can swap and which you'll need to buy.

            There are some shims that have an "x" in the measurement - 2.75x. That means it's slightly larger than 2.75. Those can be helpful when you're right on the edge and want to get it more toward the middle of the acceptable tolerance, but don't worry about it.

            Be sure to put the shim in with the measurement side down so the cam doesn't wear it off. Also, do not use a magnet to remove the shims. They are hardened steel and easily magnetized. You don't want them to come out of their seats because they're sticking to the cam.

            Good luck...

            Comment


              #7
              Originally posted by ptm

              ----------------------------------
              turn crank until
              #1 exhaust cam lobe pointing forward parallel with the top of the head
              - check #1 exhaust
              - check #2 exhaust

              rotate crank 180 degrees
              #1 intake cam lobe pointing up perpendicular to the top of the head
              - check #1 intake
              - check #2 intake

              rotate crank 180 degrees
              #4 exhaust cam lobe pointing forward parallel to the top of the head
              - check #3 exhaust
              - check #4 exhaust

              rotate crank 180 degrees
              #4 intake came lobe pointing up perpendicular to the top of the head
              - check #3 intake
              - check #4 intake
              I think this procedure is for the 16 valve models... mine is an 8 valve (I forgot to mention this, sorry )

              Thanks for all the other info by the way, it's very useful.

              Just out of curiosity, so I can better understand how my engine works, what would be some of the expected symptoms that I would get if I were to leave the shims like they are? I'm actually not planning to change the affected shims until next month, but I am planning to re-build the carbs before then and then will try to run the bike.

              Thanks again.

              Comment


                #8
                Just food for thought. If you find that you are not going to need certain shims, call a local dealer/shop and see if they'd be willing to swap shims. The Suzuki dealer here was willing to do that. Might save you some money.

                Brad tt

                Comment


                  #9
                  BEXABARR, no that procedure is for an 8 valve engine (count the valves)

                  number 2 & 3 exhaust clearance is a little too wide so they will be a little noisy

                  number 4 exhaust MAY be a little to tight you need a .03mm feeler gauge to be sure, if its less than .00mm it will hold the valve open and and probably have low compression in that cylinder which may show up as a miss or possibly it may burn the valve (that you don't want)

                  you can't tell if you can swap shims without taking them out and looking on the back side for the thickness of EACH shim or checking the thickness of them with a micrometer, they come in different thickness from 2.30mm to 3.00mm in .05mm increments.

                  hope this helps.
                  De-stinking Penelope http://thegsresources.com/_forum/sho...d.php?t=179245

                  http://www.thegsresources.com/_forum...35#post1625535

                  Comment


                    #10
                    Thanks guys, I will check my shims clearance today. I don't know why I thought that was a procedure for a 16 valve bike, thanks for the clarification. I did find that 2 and 3 exhaust were 2.70mm that means I likely need to get 2.75mm shims. I'm going to call my Suzuki dealer today to see if they will swap shims, or at least what prices they have them at. Thanks again!

                    Comment


                      #11
                      As long as your in there check the #4 exhaust thickness and pick up an extra shim .05mm thinner...
                      De-stinking Penelope http://thegsresources.com/_forum/sho...d.php?t=179245

                      http://www.thegsresources.com/_forum...35#post1625535

                      Comment


                        #12
                        Have you measured compression on each cylinder?
                        If the bike doesn't smoke then your rings are OK.
                        Then
                        Low compression = zero valve clearance

                        If compression is within spec for each cylinder then there's no immediate need for valve adjustment.

                        Comment


                          #13
                          I need to get a compression gauge. There are a few cheap ones out there, the spark plug gap is 14mm, 18mm or what?

                          But from what I gather, it is better to have shims that are too loose than have ones that are too tight.

                          Comment


                            #14
                            The spark plug threads are 14mm.


                            Where y'at, anyway? Might be a GS-er around with some extra shims.
                            1983 GS850G, Cosmos Blue.
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                            Comment


                              #15
                              I'm going to get a lot of s*** from this ... I'm in nothern NY (Finger Lakes region). But I only need a few, I'll probably just end up buying them. Thanks.

                              Comment

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