Announcement

Collapse
No announcement yet.

is this a possible loose cam chain on My GN250 single cyl?

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

    is this a possible loose cam chain on My GN250 single cyl?

    This is the bike cold (needed a little choke) I'm thinking this rattling / tinkling is my cam chin, but don't know?

    Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.


    should I just pull off the cam chain adjuster inspect it and fit it back on...are there any things to look out for on a worn/broken adjuster?

    Cheers

    #2
    Kind of hard to tell, as most phones have pretty good noise cancelling abilities.

    Three likely areas that might cause similar noises:
    1. Loose valves
    2. Loose cam chain
    3. Loose clutch basket

    For the valves, check the clearances. I have not worked on a GN, but I think they are similar to the GS.

    For the chain tensioner, again, it's probably similar to the GS, one of the biggest problems is that somebody installed it incorrectly. Before removing it, loosen the locknut, tighten the set screw, back the set screw out 1/4 turn, lock it in that position with the locknut. See if the noise is gone.

    For the clutch, you will have to pull the cluch cover (requires a gasket for re-assembly) and the pressure plate, along with all the disks. Keep the disks in the same order and orientation, so they go back in exactly the same way. Tighten the nut that holds the basket to the shaft, put everything back together.

    If the engine still makes noise, it might be "normal".

    .
    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
      Paul, did you recently check your valve adjustment? i think i recall you posting a thread up about it. did it rattle like that before you did the adjustments?
      if not i suggest you recheck your valve clearances again
      1978 GS1085.

      Just remember, an opinion without 3.14 is just an onion!

      Comment


        #4
        Originally posted by Agemax View Post
        Paul, did you recently check your valve adjustment? i think i recall you posting a thread up about it. did it rattle like that before you did the adjustments?
        if not i suggest you recheck your valve clearances again
        Yes I have been trying to master valve adjustments and perhaps they are a little tight still... I just had a look now, and the weathers so cold the oil doesn't want to show me the TDC mark, so I'll order a filter, change the oil and have another go in couple of days. Not sure if it rattled so bad before, but the chain tensioner doesnt look like it been touched in years

        I'll report back when I've had another go at it
        Thanks guys,

        Comment


          #5
          Originally posted by Paul View Post
          Yes I have been trying to master valve adjustments and perhaps they are a little tight still... I just had a look now, and the weathers so cold the oil doesn't want to show me the TDC mark, so I'll order a filter, change the oil and have another go in couple of days. Not sure if it rattled so bad before, but the chain tensioner doesnt look like it been touched in years

          I'll report back when I've had another go at it
          Thanks guys,
          i dont understand how your oil wont show you TDC? am i missimg something here???????
          1978 GS1085.

          Just remember, an opinion without 3.14 is just an onion!

          Comment


            #6
            Originally posted by Agemax View Post
            i dont understand how your oil wont show you TDC? am i missimg something here???????
            I was wondering that, too, besides the fact that tight valves won't make noise.

            If the valves are making noise, it's because they are too LOOSE, not tight.

            .
            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


              #7
              Originally posted by Agemax View Post
              i dont understand how your oil wont show you TDC? am i missimg something here???????
              The TDC mark is on the LH side of the engine on the outside of the rotor. You remove a small bolt to look through a hole so it can be a bit tricky. Because it's bathed in oil the oil, when it's cold, can stick on the outside and mask the TDC mark.
              79 GS1000S
              79 GS1000S (another one)
              80 GSX750
              80 GS550
              80 CB650 cafe racer
              75 PC50 - the one with OHV and pedals...
              75 TS100 - being ridden (suicidally) by my father

              Comment


                #8
                Originally posted by hampshirehog View Post
                The TDC mark is on the LH side of the engine on the outside of the rotor. You remove a small bolt to look through a hole so it can be a bit tricky. Because it's bathed in oil the oil, when it's cold, can stick on the outside and mask the TDC mark.
                ah, now i understand. thanks Wally......
                1978 GS1085.

                Just remember, an opinion without 3.14 is just an onion!

                Comment


                  #9
                  That engine design is really reliable (unburstable even) but they do have a few weakpoints and you have probably copped for one of them. The camchain tensioner can stop working with a build up of gunk, get worn etc. It is worth, like you thought, pulling the thing off and cleaning it up. There are aftermarket tensioners that you set manually - they sort the problem and are lot cheaper than a new OEM.

                  Valve clearances need sorting regularly. As we know they are so often just ignored. No biggy as they are conventional screw and locknut type and easy to get at.

                  And change the oil and filter a lot. That little engine has to work hard and the oil capacity is only a little more than a thimbleful to start with.

                  And of course finish. Some / most of them (all of them?) were put together under licence in China and the build quality is a bit iffy. The exhausts and mudguards will rust before your eyes. Fortunately replacement parts are dirt cheap.
                  79 GS1000S
                  79 GS1000S (another one)
                  80 GSX750
                  80 GS550
                  80 CB650 cafe racer
                  75 PC50 - the one with OHV and pedals...
                  75 TS100 - being ridden (suicidally) by my father

                  Comment


                    #10
                    Originally posted by hampshirehog View Post
                    That engine design is really reliable (unburstable even) but they do have a few weakpoints and you have probably copped for one of them. The camchain tensioner can stop working with a build up of gunk, get worn etc. It is worth, like you thought, pulling the thing off and cleaning it up. There are aftermarket tensioners that you set manually - they sort the problem and are lot cheaper than a new OEM.

                    Valve clearances need sorting regularly. As we know they are so often just ignored. No biggy as they are conventional screw and locknut type and easy to get at.

                    And change the oil and filter a lot. That little engine has to work hard and the oil capacity is only a little more than a thimbleful to start with.

                    And of course finish. Some / most of them (all of them?) were put together under licence in China and the build quality is a bit iffy. The exhausts and mudguards will rust before your eyes. Fortunately replacement parts are dirt cheap.
                    Well, I feel a bit silly, but I changed the oil/filter, fitted a new cush drive, and some second hand shocks as the centre eye on one of the shocks was missing from the previous owner, so thats all good, pulled out the chain tentioner and rechecked the valves and seemed ok, this time I happened to be wearing my hearing aid and as the engine was cold I was able to touch the engine and narrowed it down the a loose heat shield that was rattling on the down pipe so alls good!

                    Comment

                    Working...
                    X