Announcement

Collapse
No announcement yet.

WTF? I'm so tired of this game....

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

    WTF? I'm so tired of this game....

    So many moons ago I delved into the carbs and all the joy THAT brings.
    After going to pods, jetting, and many many plug chops, with somewhat successful results, I decided it wasn't performing as well as it could/should. So I reverted back to stock settings, airbox, etc...
    And now it runs like the crap. What is going on?
    Replaced boot o-rings
    Thoroughly cleaned carbs.
    Soft rubber everywhere.
    Good compression on all 4 (130-145)
    Strong spark, 12.4 v at the coils.
    Fuel delivery confirmed (all 4 pipes get hot, all 4 bowls drain gas)
    Plugs sort of a rusty brown.

    So this is what the new iteration is doing: Approx 5k rpm, 55-60mph, throttle just cracked enough to maintain speed, it kind of surges as though it's running out of gas. Whack the throttle and it responds appropriately, i.e., accelerates about like it should, but upon closing the throttle will sometimes pop and backfire.
    If I gotta pull those damm carbs out again I think I'm going to sell the stupid thing.

    #2
    CV carbs - makes me think damaged diaphragms if you're sure you've set everything to stock (did you put the needle height back right?).
    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


      #3
      Originally posted by Smokinapankake View Post
      So many moons ago I delved into the carbs and all the joy THAT brings.
      After going to pods, jetting, and many many plug chops, with somewhat successful results, I decided it wasn't performing as well as it could/should. So I reverted back to stock settings, airbox, etc...
      And now it runs like the crap. What is going on?
      Replaced boot o-rings
      Thoroughly cleaned carbs.
      Soft rubber everywhere.
      Good compression on all 4 (130-145)
      Strong spark, 12.4 v at the coils.
      Fuel delivery confirmed (all 4 pipes get hot, all 4 bowls drain gas)
      Plugs sort of a rusty brown.

      So this is what the new iteration is doing: Approx 5k rpm, 55-60mph, throttle just cracked enough to maintain speed, it kind of surges as though it's running out of gas. Whack the throttle and it responds appropriately, i.e., accelerates about like it should, but upon closing the throttle will sometimes pop and backfire.
      If I gotta pull those damm carbs out again I think I'm going to sell the stupid thing.
      you need to pull the carbs again. REMEMBER: These bikes came from the FACTORY LEAN. This means if you reverted back to STOCK, you're a touch lean. Pull the main, bump it up one size. Shim the needles. A question for you tho. When you had it modded with the pods and pipe, did you drill the slides? If so, this is going to make you lean out also.

      Comment


        #4
        check the petcock to see if it feeding enough fuel to carb when you hit 5K rpm. It might be clogged and therefore can't deliver enough fuel when the bike needs it at 5k rpm.

        Comment


          #5
          Did you adjust the valves?? If they haven't been checked yet, this is your culprit until proven otherwise.
          Yamaha fz1 2007

          Comment


            #6
            TCK,

            Did not drill slides as I'm very leery of mods that are permanent.
            It's such a Gawd damm pain to pull the carbs! It's a pain to do a simple plug chop because you gotta pull bodywork. On the side of the road in 98 degree weather. Ugh.

            I don't get why factory stock exhaust, carb settings, etc... would be so sensitive. I mean, they sent these things all over the world (except the good ole US of A), so what gives? I shouldn't have to jet for elevation, right? I'm at approx. 4500'.

            I can move the needles around, it has multiple slots as its a JDM motorcycle. So do I move them up or down? Up would lean it out more, down would richen.....Probably move them down. And I shouldn't need to do anything with the pilot jet.

            Diaphrams are solid, no rips tears or even pinholes.
            Thanks for your patience, I could really use some right now.

            Does anybody know if these have the reusable rubber valve gasket, like the 550's did?

            Comment


              #7
              Hey in Utah:

              I'm not sure what you did to the carb/jets when you decided to go with PODS...but I would bet my collection of pubic hairs that you simply didn't get the jetting correct. I am also riding at 4000k elevation.

              What sort of pods did you replace the airbox with and what sort of changes did you make on the main jets??

              This situation my have a relatively easy fix. (Then again it may not; but I'm willing to hear you out).

              Comment


                #8
                Originally posted by Smokinapankake View Post
                TCK,

                Did not drill slides as I'm very leery of mods that are permanent.
                It's such a Gawd damm pain to pull the carbs! It's a pain to do a simple plug chop because you gotta pull bodywork. On the side of the road in 98 degree weather. Ugh.

                I don't get why factory stock exhaust, carb settings, etc... would be so sensitive. I mean, they sent these things all over the world (except the good ole US of A), so what gives? I shouldn't have to jet for elevation, right? I'm at approx. 4500'.

                I can move the needles around, it has multiple slots as its a JDM motorcycle. So do I move them up or down? Up would lean it out more, down would richen.....Probably move them down. And I shouldn't need to do anything with the pilot jet.

                Diaphrams are solid, no rips tears or even pinholes.
                Thanks for your patience, I could really use some right now.

                Does anybody know if these have the reusable rubber valve gasket, like the 550's did?
                hmm, I may be high but I do believe raising the needles richens the mixture, lowering leans it. If your needles are raised, more fuel is allowing to come through the emulsion tubes and into the motor.

                Comment


                  #9
                  I should have clarified - moving the CLIPS down will raise the needle, richening, while raising the CLIPS will lower the needle, leaning out.
                  Correct?

                  Comment


                    #10
                    Originally posted by Smokinapankake View Post
                    TCK,

                    Did not drill slides as I'm very leery of mods that are permanent.
                    It's such a Gawd damm pain to pull the carbs! It's a pain to do a simple plug chop because you gotta pull bodywork. On the side of the road in 98 degree weather. Ugh.

                    I don't get why factory stock exhaust, carb settings, etc... would be so sensitive. I mean, they sent these things all over the world (except the good ole US of A), so what gives? I shouldn't have to jet for elevation, right? I'm at approx. 4500'.

                    I can move the needles around, it has multiple slots as its a JDM motorcycle. So do I move them up or down? Up would lean it out more, down would richen.....Probably move them down. And I shouldn't need to do anything with the pilot jet.
                    Diaphrams are solid, no rips tears or even pinholes.
                    Thanks for your patience, I could really use some right now.

                    Does anybody know if these have the reusable rubber valve gasket, like the 550's did?
                    Ok, you got that backwards, if you move the needle up a notch or shim it up you will be richer when the slide goes up.
                    If you move the needle down a notch or remove a shim, you will lean it up more when the slides go up.

                    Comment


                      #11
                      Originally posted by Smokinapankake View Post
                      I should have clarified - moving the CLIPS down will raise the needle, richening, while raising the CLIPS will lower the needle, leaning out.
                      Correct?
                      If you move the clips towards the pointy end, you will get richer, if you move the clip towards the blunt end, you will be leaner

                      Comment


                        #12
                        Originally posted by Smokinapankake View Post
                        TCK,

                        Did not drill slides as I'm very leery of mods that are permanent.
                        It's such a Gawd damm pain to pull the carbs! It's a pain to do a simple plug chop because you gotta pull bodywork. On the side of the road in 98 degree weather. Ugh.

                        I don't get why factory stock exhaust, carb settings, etc... would be so sensitive. I mean, they sent these things all over the world (except the good ole US of A), so what gives? I shouldn't have to jet for elevation, right? I'm at approx. 4500'.

                        I can move the needles around, it has multiple slots as its a JDM motorcycle. So do I move them up or down? Up would lean it out more, down would richen.....Probably move them down. And I shouldn't need to do anything with the pilot jet.

                        Diaphrams are solid, no rips tears or even pinholes.
                        Thanks for your patience, I could really use some right now.

                        Does anybody know if these have the reusable rubber valve gasket, like the 550's did?
                        Yes, you DO have to adjust for elevation. When a bike came into a dealership, they prepped it for sale in their shop. Meaning, they tuned it to get it running for the area of the world it was in. They dont just roll em off a truck and put gas in em and fire em up. This elevation would actually RICHEN your mixture, as compared to sea level or lower elevation, as the higher you go, the thinner the air becomes. Move the clip DOWN one notch, which RAISES the needle, fattening the mix. Set your screws to 2.5 turns out on the outer cylinders, and 2.75 out on the inner. See how that works for you Also, ASSURE your float levels are set as well. This played a big part in how my bike was running. They were close, but the more exact you can make them, the more balanced everything is. Did you sync them when you put them back together as well? And YES, Valve clearance could definately be playing a role in this as well. Dont thank me, glad to pass on what knowlege i have gained

                        Comment


                          #13
                          Well said.......I don't think it gets any simpler than that!

                          Comment


                            #14
                            Originally posted by Smokinapankake View Post
                            TCK,

                            I don't get why factory stock exhaust, carb settings, etc... would be so sensitive. I mean, they sent these things all over the world (except the good ole US of A), so what gives? I shouldn't have to jet for elevation, right? I'm at approx. 4500'.
                            Wrong answer clyde...

                            As a matter of fact, the closer to a perfect tune on the carbs, the more you have to adj for elevation.

                            From sea level to 4,500-feet is a significant change in rich vs lean settings.

                            From what I have been able to determine you get the float bowls set perfectly first thing.

                            Then wide open blasts down the road by whacking open the throttle after a good cleaning of the plugs and hitting the kill switch at wide open throttle (stay off the freeways for this) so that you can inspect each plug.

                            Get them all to be light tan.

                            After this step it is mid range roll on, by marking the hand throttle from 1/4 to 3/4 and staying in that range, wind it through this range to compare the mid range settings, lowering/raising the clip (start with manufactures recommended setting for the e-clip).

                            Once all plugs are tan again, then go the idle adj by turning set screws until they slightly bottom out, and then backing out the "air" screws until you meet the manufactures guidelines. (around 2 turns out... various models will be 1.5-2.5 turns out).

                            That ought to do it....

                            [Edit] Ooppssss Just read Cafekid posts...doh! What he said!
                            Last edited by Guest; 07-10-2008, 10:18 PM.

                            Comment


                              #15
                              Originally posted by Joe Guilbeau View Post
                              Wrong answer clyde...

                              As a matter of fact, the closer to a perfect tune on the carbs, the more you have to adj for elevation.

                              From sea level to 4,500-feet is a significant change in rich vs lean settings.

                              From what I have been able to determine you get the float bowls set perfectly first thing.

                              Then wide open blasts down the road by whacking open the throttle after a good cleaning of the plugs and hitting the kill switch at wide open throttle (stay off the freeways for this) so that you can inspect each plug.

                              Get them all to be light tan.

                              After this step it is mid range roll on, by marking the hand throttle from 1/4 to 3/4 and staying in that range, wind it through this range to compare the mid range settings, lowering/raising the clip (start with manufactures recommended setting for the e-clip).

                              Once all plugs are tan again, then go the idle adj by turning set screws until they slightly bottom out, and then backing out the "air" screws until you meet the manufactures guidelines. (around 2 turns out... various models will be 1.5-2.5 turns out).

                              That ought to do it....
                              Not always. As he's said, his plugs looked good. MY plugs looked good in my 1100G. But it still wasnt quite running right at high speed roll ons. Smokin, give the adjustments i suggested a shot. See if it works for you. At your elevation, you MAY want to try the outer cylinders screws at 2.25 turns out and the inner at 2.5 out, since you'll naturally be just a tad richer than me.

                              Comment

                              Working...
                              X