Announcement

Collapse
No announcement yet.

Occasional backfiring; loss of power; lurching

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

    Occasional backfiring; loss of power; lurching

    Hey,

    So I just did a major valve adjustment and I noticed on the highway (55+) i get a little bit of lurching when cruising. Also, when I twist the throttle hard, I occasionally get a bit of backfire (very small). Also,when under the load of 4th or 5th gear, the power just isn't there like it should be.

    Could I have mucked the valve adjustment? Should I crack it open again and check?

    Also, am I correct in thinking I have to valve adjustment when it is completely cold?

    Thanks in advance...
    Tags: None
    #2
    Yes to all. If it didn't do that before, you got something wrong.
    Let the bike sit overnight before adjustment.

    Comment

      #3
      Are these typical symptoms of a bad valve adjustment?

      Comment

        #4
        Hi Sky,

        I may be off base here, but depending on how bad your valves were off before (what do you mean by major adjustment?), you've changed the restriction of air flow into and out of the cylinders. You probably would be wise to resync the carbs as well.

        Comment

          #5
          I did resync them too. Hmmm.

          Comment

            #6
            Did I mention it is backfire through the carbs?

            OK, so I have done a lot of thinking (and soul searching) and figured I'm going to continue playing with the mixture screws because that made the problem 80% better. Maybe I am not there yet...

            I'm sure I did the valve adjustment correctly, so I am not going to crack that open yet.

            I am also going to run some Seafoam through there because I'm sure when the valves were maladjusted, there had to be some buildup and gunk in there. I'll run it a bit more and see where she is.

            Any more advice regarding backfiring through carbs would be helpful.

            Comment

              #7
              How do you spark plugs look?

              You may have an air leak causing problems.

              Have you cleaned the carbs recently?
              1978 GS 1000 (since new)
              1979 GS 1000 (The Fridge, superbike replica project)
              1978 GS 1000 (parts)
              1981 GS 850 (anyone want a project?)
              1981 GPZ 550 (backroad screamer)
              1970 450 Mk IIID (THUMP!)
              2007 DRz 400S
              1999 ATK 490ES
              1994 DR 350SES

              Comment

                #8
                FIGURED IT OUT!!!

                So, before I started the bike up this morning to play around with it, I cleaned off a little oil with some simple green then rinsed it with water. I started it up and started to look at the carbs while backfiring. Because it was cold and wet, i saw puffs of smoke coming from the intake boots. BING!

                I took the carbs off again and one of the boots came with it! the three others fell right off the metal part. Shi**y.

                So now I need to get some new boots. Any suggestions on lowest price?

                Comment

                  #9
                  Check with www.Z1enterprises.com

                  Comment

                    #10
                    They do not have them. I think I need OEM.

                    Comment

                      #11
                      bikebandit is where i get all of my oem parts

                      Comment

                      Previous template Next
                      Working...
                      X