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.23 intake valve clearance

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  • .23 intake valve clearance

    How bad is having .23 intake valve clearance on 3 valves? I know the recommended clearance is .16-.2

    When I reshimmed last, I was sure I had good tolerances. What could cause the clearances to increase? Am I looking at possible bad valves?
    Mike C
    Lake Orion, Michigan
    '78 XS1100E

    Here I am! Where are you?

  • #2
    Are you 100% positive that you got the valve shims correct last time?

    Usually, valve clearances decrease as a result of the valves wearing into the valve seats. This reduces the gap and means ever thinner shims are usually needed (hence there being not much demand for the thicker shims).

    Your valve clearances would appear to have increased. This is not usual and makes me wonder if you set them right last time. If you did, then there must be wear on the cam lobes or the shims themselves. Is everything OK with your oil/oil pressure etc?
    XS1100F 1980 European model. Standard. Dyna coils. Iridium plugs. XS750 final drive (sometimes). Micron fork brace. Progressive front springs. Geezer regulator/rectifier. Stainless 4 into 2 exhaust. Auto CCT (Venturer 1300) SOLD. New project now on the go. 1980 European model.

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    • #3
      James,

      Thanks for the reply.

      Last time I did them was the first time, so there's a very real possibility I screwed something up. It's been about 4000 miles since then of seemingly normal operation, but who knows.

      I haven't noticed any oil pressure issues, but I'm not sure what I'd even be looking for. The bike does burn a bit of oil, about a quart every 700 mile highway trip.

      Full disclosure time: When I did the shims last time I used the shim tool. However, I didn't realize that I wasn't supposed to rotate the cams without a shim in the bucket and managed to scratch up the edges of a few of the cam lobes. I cleaned out the offending slivers of metal, but haven't noticed any other symptoms.

      How bad have I screwed the pooch here? Should I get 3 new shims and hope for the best?
      Mike C
      Lake Orion, Michigan
      '78 XS1100E

      Here I am! Where are you?

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      • #4
        I should mention measurements are with feeler gauges and the .23 is going in with some small resistance. .25 will not go in.

        I just mic'd the feelers, the .23 mic'd at .236 and the .2 mic'd at .204 so they're in the ballpark.
        Last edited by Fix; 07-09-2012, 05:22 PM.
        Mike C
        Lake Orion, Michigan
        '78 XS1100E

        Here I am! Where are you?

        Comment


        • #5
          Originally posted by Fix View Post
          How bad is having .23 intake valve clearance on 3 valves? I know the recommended clearance is .16-.2

          When I reshimmed last, I was sure I had good tolerances. What could cause the clearances to increase? Am I looking at possible bad valves?
          I assume this is intake valves? You're .001" over, I wouldn't worry about it at all. You'll have a bit more noise, but the adjustement will 'come' to you (close up with wear) so you'll just have a longer time before it needs it again.

          As to the cause, I've found that using metric measurements and that shim chart is usually the culprit...
          Fast, Cheap, Reliable... Pick any two

          '78E original owner - resto project
          '78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
          '82 XJ rebuild project
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          Other current bikes:
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          • #6
            Originally posted by crazy steve View Post
            As to the cause, I've found that using metric measurements and that shim chart is usually the culprit...
            Guilty as charged.
            Mike C
            Lake Orion, Michigan
            '78 XS1100E

            Here I am! Where are you?

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            • #7
              Just skip the chart and do the math the ol'fashon way and most importantly, measure the as-left clearance to make sure your math is right.
              '79 XS11 F
              Stock except K&N

              '79 XS11 SF
              Stock, no title.

              '84 Chevy K-10 "Big Blue"
              GM 350, Muncie SM465, NP208, GM 10 Bolt with 3.42gears turnin 31x10.5 Baja Claws

              "What they do have is an implacable, unrelenting presence and movement that bespeaks massive power lurking behind paint and chrome. They don't wail like a screeching ninja, the don't rumble like a harley. They just growl like a spactic, stressed out badger waiting to rip your face off and eat your soul." Trainzz~RIP~

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