Announcement

Collapse
No announcement yet.

More questions

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

  • #16
    Guys,

    I am not the experts that you all are but I ponder this: If he has any clearance at all the valves are closing right? Maybe not when the engine is running. maybe like a floating valve?
    79 XS1100 f (BIGDOG)
    80 XS650 Special
    85 KAW 454 LTD
    Dirty Dan

    Comment


    • #17
      Yes, and maybe, that's what I am thinking. He had the exhaust valves replaced. Intakes were not replaced, and he can't get a 0.06mm feeler under the intakes. The compression is too low on 3 cylinders and adding oil doesn't change that. But there is some compression. So when the engine is cold the intakes *might* be closing just enough for a compression test.

      But if any valves are staying open from the clearance numbers teck says he has the intakes would be suspect. Wouldn't that light up the carbs? Backfire?

      Ken mentioned the wrong feeler gauge, might be something there. Spec is Exh = 0.21- 0.24 mm or .008" - .0095".
      Intake is 0.16 - 0.20 mm or .006" - .0079".
      The guy could have used a .06 mm feeler thinking it was .006", but that would still give .002" clearance.

      What else might cause low compression readings? Head gasket leak? If the guy who did the valves had the wrong feeler gauge, what else might be wrong? Valve seat ground wrong?

      Could the cam be out of time with the pistons? The cam chain was off, teck says the dots line up on the cam sprockets, but is the piston at TDC?

      Need more info I guess.
      Marty in NW PA
      Gone - 1978E - one of the first XS11 made
      Gone - 2007A FJR - the only year of Dark Red Metallic
      This IS my happy face.

      Comment


      • #18
        Well, I would be looking at the head gasket. I had lost compression on two and three down to 90 lbs. Brand new everything in the motor. Realized that I had put the gasket in that goes between the jugs and the head for the cam chain cavity but the head gasket I had was made to not use one. I retorqued the head three differnet times after warming the engine up and finally all the compression was back. Runs great now.
        79 XS1100 f (BIGDOG)
        80 XS650 Special
        85 KAW 454 LTD
        Dirty Dan

        Comment


        • #19
          Valve issues

          Hi

          Okay, I'm off to remeasure with the cam lobes at the lowest point. I'm going to pull the cams then remove the shims to identifie the size.

          Stay tuned
          Tim Lowe
          "Teck"
          1979 xs1100 Special

          Comment


          • #20
            Measurements and Shim sizes

            Hello

            Okay measured, tested and pulled the shims from my 79 xs1100 special.

            Compression

            1-110 2=85 3=72 4= 80

            Cam to shim pad measurements

            Intake
            0.06 mm the smallest I have and I couldn't get the feeler to budge

            Current shim sizes (intake)

            1=265 2=270 3=270 4= 280

            Exhaust

            Cam to shim pad measurements

            1-0.08 mm okay 2,3,4 = 0.06 the smallest I have and I couldn't get the feeler to budge

            Current shim pad size (Exhaust)

            1=290 2=290 3=295 4=295

            What should I be doing?
            Tim Lowe
            "Teck"
            1979 xs1100 Special

            Comment


            • #21
              Let's assume you have some compression, and the valves-shim clearance is 0 for those where you can't get .06 under. You will probably have to do this more than once, since you really don't have a starting number. You need thinner pads.

              Since you don't have excess clearance, simply subtract the nominal spec from the pad you have, round to nearest 05.

              Intakes - clearance is 0.00, spec is .19:
              #1 - 265 -19 = 244 = Pad #245
              #2 - 270 -19 = 251 = 250
              #3 - 270 -19 = 251 = 250
              #4 - 280 -19 = 261 = 260

              Exhausts
              #1 - 290 -15 = 275
              #2 - 290 -23 = 267 = 265
              #3 - 295 -23 = 272 = 270
              #4 - 295 -23 = 272 = 270

              This should get you in the ball park, assuming nothing else is wrong. Be sure after you replace the pads to turn the engine a couple of times by hand to settle the pads in. Then check the clearance. If it is close to specs then check compression.
              Marty in NW PA
              Gone - 1978E - one of the first XS11 made
              Gone - 2007A FJR - the only year of Dark Red Metallic
              This IS my happy face.

              Comment


              • #22
                Re: Measurements and Shim sizes

                Originally posted by teck_mountain
                Hello

                Okay measured, tested and pulled the shims from my 79 xs1100 special.
                Cam to shim pad measurements
                Intake
                0.06 mm the smallest I have and I couldn't get the feeler to budge

                Current shim sizes (intake)
                1=265 2=270 3=270 4= 280

                Exhaust
                Cam to shim pad measurements
                1-0.08 mm okay 2,3,4 = 0.06 the smallest I have and I couldn't get the feeler to budge

                Current shim pad size (Exhaust)
                1=290 2=290 3=295 4=295

                What should I be doing?
                Okay, book says you want ~.16-0.20mm INTAKE clearance, couldn't get the .06mm gauge inbetween, but there is a small gap, possibly .03-.04, so add that to the lowest clearance of .16 would get you the max, so a drop in shim size of 15 from each intake so you would want to put in:
                250; 255; 255; 265 for intakes!
                So far you can swap #1 shim to # 4 place.

                Exhaust range 0.21-0.25mm, #1 has .08, subtract that from .21 equals .13...round to .15 from #1 size gets you 275.
                Again, estimating the others clearances around .03-.05mm, from 0.21 again gets you about .15, so reduce the other shims also by 15:
                #1=275; #2=275; #3=280; #4=280

                You can use the old #4Int. shim for #4 Exh,
                You could try one of the 270Int shims in #2 Exh....might be closer to the .25 clearance than the .21, but it looks like you'll need to trade 5 or 6 shims!
                HTH. T.C.
                T. C. Gresham
                81SH "Godzilla" . . .1179cc super-rat.
                79SF "The Teacher" . . .basket case!
                History shows again and again,
                How nature points out the folly of men!

                Comment


                • #23
                  Feeler Guages.

                  Instead of all this playing around and guessing go out and spend a couple of dollars and buy a new set of feeler guages. A set that starts at .001 or .0015. Then you will know where you are and can make sensible decisions on what sizes to put in the first time around.
                  Ken/Sooke

                  Comment


                  • #24
                    What, quit our charades?
                    Good idea Ken.
                    Marty in NW PA
                    Gone - 1978E - one of the first XS11 made
                    Gone - 2007A FJR - the only year of Dark Red Metallic
                    This IS my happy face.

                    Comment


                    • #25
                      Ken's suggestion

                      Good one

                      However, I have the bike apart so will ball park it. Thanks to all for the help. I will let you know the outcome. Hopefully tomorrow evening
                      Tim Lowe
                      "Teck"
                      1979 xs1100 Special

                      Comment


                      • #26
                        update

                        good day all

                        new shims are in and I have 145 compression in all four.
                        Tim Lowe
                        "Teck"
                        1979 xs1100 Special

                        Comment


                        • #27
                          Wow that was fast! Good for you!! Now how's it run?
                          Marty in NW PA
                          Gone - 1978E - one of the first XS11 made
                          Gone - 2007A FJR - the only year of Dark Red Metallic
                          This IS my happy face.

                          Comment


                          • #28
                            Update

                            Hi

                            Had to kick start the thing. Started on the third kick. ran rough for the first 10 to 15 minutes but after adjusting the idle and a couple of sight adjustments to the idle mixture screw?? it seemed to settle in.

                            I had to put a new left control on and I cann't get the head light to work. any suggestions were to start?
                            Tim Lowe
                            "Teck"
                            1979 xs1100 Special

                            Comment


                            • #29
                              Hey there Teck,

                              Congrats on the valve shim work and great compressions! Okay, kick starting it sounds like you either ran the battery down, or the charging system isn't kicking in, and the headlight is designed to be switched on when a relay and diode senses the engine is running and charging current is going to the battery, so after you start the bike, does the headlight come on?

                              Secondly, you can take a jumper wire and direct test the bulb to make sure it's not burned out. Are your fuses really good, glass fuses can be misleading, pull them, check the holders, etc.!!

                              With it running at 4-5k, are you getting ~14 volts at the battery on a voltmeter, if only 12....then your charging system isn't right, could be just corrosion in connectors, could be voltage reg, etc., there are several threads and tech tips for checking these things, I'm definitely not a guru in this, or for that matter, any area!!
                              Good Luck. T.C.
                              T. C. Gresham
                              81SH "Godzilla" . . .1179cc super-rat.
                              79SF "The Teacher" . . .basket case!
                              History shows again and again,
                              How nature points out the folly of men!

                              Comment


                              • #30
                                Wow

                                Thanks for the help regarding my head light. The wire colors faded enought that a couple of the green look brown. Any way I was able to get things fixed.

                                Had it out for a run around the block. Wow, more power and pep than I remember. Still a little wonkie but I it may be related to low fuel. Will try again tomorrow.

                                I initially set the carbs at 1.25 turns from a slightly seated positon. However, I'm finding that the bike seems to run better at a half turn out. can this be right?
                                Tim Lowe
                                "Teck"
                                1979 xs1100 Special

                                Comment

                                Working...
                                X