Announcement

Collapse
No announcement yet.

Story so far and next steps..

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    Story so far and next steps..

    Ok.. So I have a 1981 GS450TX. The history is that is sat in a barn for 25 years with no love. I moved the bike to my garage and started giving it some love..

    Replaced spark plugs, Air filter and oil.
    Bike compression was 140-150 on each cylinder.

    Bike was hanging at about 3500 RPM and decided to rebuild carbs and O-rings as well as install new O-rings in the intake boots.

    Removed Engine to allow for removal of Intake boots.

    Replaced intake O-rings and soaked carbs for 24 hours. Cleaned carbs and replaced all O-Rings.

    Reinstalled all components and the bike ran like crap. Bogged at all levels and need starter fluid to even get running.

    New compression test shows that both cylinders are now running at 90 PSI compression.

    Current belief is that the Head Gasket may have blown of a vavle adjustment is needed.

    Current plan of action.
    Perform a Valve adjustment. Once complete test compression.

    If compression still low then add marvel mystery oil to cylinders to see if compression increases. If no increase then head gasket. If increase then piston rings are to blame.

    I believe this may all arise from the need for a new head gasket but another factor is that I had to have the valve cover bolts removed using and EDM machine as they broke during removal. This may have introduced metal shavings and I am concerned that the compression issue is due to metal gouging the piston area.. Is there anyway to rule this out..

    At this point I feel like my only option if the vavle adjustment does not correct this situation is to replace the head gasket. I have no basis for this except cars and it a pain on cars so not sure what it may take for my bike.

    Let me know your thoughts or ideas here. Is the head gasket a valid troubleshooting area or should I start somewhere else?
    Tags: None
    #2
    Adjust your valves first. They'll have some bearing on your compression readings. If it's not smoking I'd be hesitant to think you've got gouges in the cylinder walls. They're cast iron, so they're gonna be tougher than some Alu shavings I'd think.

    You could simply have some sticky rings from sitting for so long. Adjust the valves then ride/run it a bit. They may loosen up and your #s come up.

    You can also do a leak down test to check your gasket if you're still suspecting it. These are much much easier to change a headgasket on provided you have a manual to follow.

    Comment

      #3
      Throw some MMO in it before you start on the valve adjustment.
      When you are finished, it will have had some time to work.

      Daniel

      Comment

        #4
        Might as well check valves now- but I'd think the running like crap is due to disturbing the carb boots and getting air leaks from 30 year old boots. Of course, this doesn't explain the compression drops. But I wouldn't expect metal shavings to show up so fast. Sort out why it's running poorly and avoid starting fluid.
        1981 gs650L

        "We are all born ignorant, but you have to work hard to stay stupid" Ben Franklin

        Comment

          #5
          As to compression ? You must have the throttle wide open !!

          Comment

            #6
            well I moved and had to let this take a break but I am back in it again. New updates are that added some oil to the cylinders and the compression increased to 100's.. This would mean that my rings are stuck or bad correct? To get a look at the the pistons and what not doesn't sound too bad, pull the valve cover and camshafts then head bolts and that should get me in there correct?? Any gotchas along the way I should know about now??
            Last edited by Guest; 03-02-2012, 11:02 AM.

            Comment

              #7
              Originally posted by mpencegs View Post
              well I moved and had to let this take a break but I am back in it again. New updates are that added some oil to the cylinders and the compression increased to 100's.. This would mean that my rings are stuck or bad correct? To get a look at the the pistons and what not doesn't sound too bad, pull the valve cover and camshafts then head bolts and that should get me in there correct?? Any gotchas along the way I should know about now??
              After 25 years the rings are bound to be sticky- might clear up with some running. Before you go looking at pistons, get to the valve adjustment now- won't take long, and you can always dig deeper later. I know you said that you clean carbs , etc., but some folks have had to do it twice. Lots of tiny little passages to clog and firm up after so many years.
              1981 gs650L

              "We are all born ignorant, but you have to work hard to stay stupid" Ben Franklin

              Comment

                #8
                so should I follow this roughly or is there one specific to the 450 floating around out there?

                http://members.dslextreme.com/users/bikecliff/images/gs850valve_adjust.pdf

                Comment

                  #9
                  Originally posted by mpencegs View Post
                  so should I follow this roughly or is there one specific to the 450 floating around out there?

                  http://members.dslextreme.com/users/...lve_adjust.pdf
                  Nothing special for the 450 valves... there's just less of them
                  1982 GS450E - The Wee Beastie
                  1984 GSX750S Katana 7/11 - Kit Kat - BOTM May 2020

                  sigpic

                  450 Refresh thread: https://www.thegsresources.com/_foru...-GS450-Refresh

                  Katana 7/11 thread: http://www.thegsresources.com/_forum...84-Katana-7-11

                  Comment

                  Previous template Next
                  Working...
                  X