Announcement

Collapse
No announcement yet.

Mysterious Clunk - GS850

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

    Mysterious Clunk - GS850

    Hey guys, been working on my project (http://www.thegsresources.com/_forum...d.php?t=172077) and a few days after putting in new clutch springs (which my or may not be relevant), there seems to be a clunking coming from inside my engine. It is usually only after it heats up. When it happening, the sound happens about every second or so and doesnt seem to be related to engine speed. I keep thinking something rotating but I cant think of anything that rotates that slow in the engine. Any suggestions on places to look or ideas would be great. Thanks.

    #2
    If it seems to come from the upper end and tends to go away if you get the engine speed over about 1500, it's probably just "cam walk".

    If that's what it is, don't worry about it.

    .
    sigpic
    mine: 2000 Honda GoldWing GL1500SE and 1980 GS850G'K' "Junior"
    hers: 1982 GS850GL - "Angel" and 1969 Suzuki T250 Scrambler
    #1 son: 1986 Yamaha Venture Royale 1300 and 1982 GS650GL "Rat Bagger"
    #2 son: 1980 GS1000G
    Family Portrait
    Siblings and Spouses
    Mom's first ride
    Want a copy of my valve adjust spreadsheet for your 2-valve per cylinder engine? Send me an e-mail request (not a PM)
    (Click on my username in the upper-left corner for e-mail info.)

    Comment


      #3
      Here's a useful trick - which you probably already know but anyway, what you do is, get a long thin screw driver. Now grab it in your fist backwards from the usual way and put your thumb over the end of the handle. Now press the other end of the screw driver to the engine cases then put your ear firmly against the top of your thumb. It's amazing how much you can hear of the engine's internal workings. I've located mysterious sounds like this on a few different engines.
      It costs nothing and only a minute so it might be worth a try.

      Comment


        #4
        Thanks for the response guys.

        Steve: I didnt think of that, I will definitely have a closer listen to the cams.

        Baz666: I did kind of try this, but the best I could get was that it seemed deep in the engine. Im going to try and narrow it down this weekend, but then thing that puzzles me is that its so slow.

        Comment


          #5
          could something gotten lose or droped in the engine case when it was apart? have you tried putting load on it?

          Comment


            #6
            BTW, I noticed you've got an MZ Baghira. I've always lusted after one of those beauties. Never seen one up close. Too bad they never sold them up here in Canada. I think they're the first ever factory supermoto.

            And about the mystery noise. Since you changed the clutch springs, I don't know how useful this is but I recall hearing about how too tight clutch springs were causing a 'deep thumping' in the rear cases of a friend's bike a few years ago. Maybe check the torque on the new springs?
            thanks,
            baz

            Comment


              #7
              Originally posted by Crazy_Russian View Post
              could something gotten lose or droped in the engine case when it was apart? have you tried putting load on it?
              I dont believe this can be the case. The only thing I had off of the engine was the valve cover.

              Originally posted by baz666 View Post
              BTW, I noticed you've got an MZ Baghira. I've always lusted after one of those beauties. Never seen one up close. Too bad they never sold them up here in Canada. I think they're the first ever factory supermoto.

              And about the mystery noise. Since you changed the clutch springs, I don't know how useful this is but I recall hearing about how too tight clutch springs were causing a 'deep thumping' in the rear cases of a friend's bike a few years ago. Maybe check the torque on the new springs?
              thanks,
              baz
              Hmm, the new springs are definitely stiffer then the ones that were in there, but I used to a torque wrench to tighten them to 8ft-lbs. I guess I can recheck them this weekend. In your friends case, did it go away or cause any major issues?

              I do really enjoy the baghira. Im just finishing up stripping the plastics down to black and polishing. Heres a pic of what it looked like when I got it.

              Comment


                #8
                My friend says that when he retorqued the new clutch springs, he thinks two might not have been tight enough and only under load would they make any noise.


                About the Baghira. It's looks great. Man, I've always lusted after one of those babies. Must be great fun in pot-hole and rut filled urban terrain. And has the Yamaha 600 or 660 thumper engine, right?
                Awesome bikes.
                thanks,
                baz

                Comment


                  #9
                  Sounds to me that the dampener springs in the back of the clutch flywheel are shot. Pull the basket and see if the sprimgs in the back are loose..any wiggle what so ever is bad.
                  Last edited by chuck hahn; 04-15-2011, 01:18 PM.
                  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


                    #10
                    Originally posted by Steve View Post
                    If it seems to come from the upper end and tends to go away if you get the engine speed over about 1500, it's probably just "cam walk".

                    If that's what it is, don't worry about it.

                    .
                    Well I believe you have have called it. Sound seems to go away at anything above 1500-1600 rpms. Is it weird that it just started?

                    Comment

                    Working...
                    X