Announcement

Collapse
No announcement yet.

Too lean?

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

  • Too lean?

    Pulled the plugs today to check their condition and noticed the insulator was very white. From my experience wrenching on my old 2-stroke dirt bikes I know that that usually means the engine is running lean.

    Couple things to note, not sure any are related to this or not:

    - I'm currently running a tank of fresh gas with about 1/2 bottle of seafoam in it to try and clean the carbs/valves since I got this bike second hand and just wanted to do it as a preventive measure. Not sure if this will have any effect on the apperance of the plugs or not, but I'm only about 1/3 of the way through that tank.

    - Bike "pops" when decelerating hard

    - I get a small backfire after shutoff from one of the pipes (sometimes both)

    - Bike has V&H pipes with a custom header for the rear cylinder but intake is stock as far as i know.

    - All emission systems have been removed.

    I've attatched a pick one of the plugs. Whats your opinions on it?

  • #2
    Seafoam will clean the plugs like that. Especially if you use the deep creep spray directly in the carb while running. Is air intake AND filter stock? Do you have cracks in intake manifold (don't go by looms get a propane torch and turn it on but don't light it...no flame just propane gas and wave it around intake while running to check for leaks). Mine pipped bad and it was the intake...I resealed with RTV and liquid electrical tape and works great...Make sure to sand the ends nice and smooth before reinstalling. Also would be good to know carb jetting.
    "I'm Ricky Bobby. If you don't chew Big Red.....then Fuck You"

    Comment


    • #3
      So when doing the intake test with the propane, what is the result if there is a leak in the intake manifold?

      Will pull the cover off the air intake and check the filter tomorrow, is there anything in particular I can look for to tell if it is an OEM Yamaha filter? I will likely pull the carb and give it a cleaning over the winter but until then I am not sure of the jetting, whether its stock or the previous owner modified it.

      Comment


      • #4
        If the idle changes while you're exposing the intake manifold area to propane then you have a leak. A new manifold is about $70 from Yamaha and you port it yourself easy enough.
        "I'm Ricky Bobby. If you don't chew Big Red.....then Fuck You"

        Comment


        • #5
          If I can confirm that the jetting is stock, and there is no intake leaks and filter is stock, is there anything that I should be checking before I start messing with richer jetting?

          These bikes have a little more to them (fuel pump, accelerator pump, TPS) than I'm used to so I'm a little lost when it comes to working with those. Most my jetting and tuning experience was on older single cylinder 2 strokes.

          Comment


          • #6
            What grade of fuel are you running? Should be using 87, no higher.

            Comment


            • Padre
              Padre commented
              Editing a comment
              Running regular 87 octane fuel.

          • #7
            without checking for a leak and confirming jetting first the rest is just guessing.

            Comment


            • #8
              Going to dig out the propane torch and check the intake this week. Got a barens kit and 37.5 pilot jet on order also just in case I do have to redo the jetting. The previous owner put on pipes without any baffle installed and I'm guessing this may be part of the issue if the jetting is stock.

              Is there any easy way to get to the jets and needle without fully removing the carb on these bikes?

              Comment


              • Lucky
                Lucky commented
                Editing a comment
                You may be able to remove the float bowl to change jets IF the screws are not too tight.
                IF a screw is really tight then use a small pair of vice grips to loosen the screw so you can finish removing it with a screwdriver.

              • Spydr
                Spydr commented
                Editing a comment
                Takes practice. Also helps a Lot if you replace the Phillips machine screws holding the bowl on with Allen screws.

                I would recommend doing it the hard way for now. Take the carb completely out and check it top to bottom.

            • #9
              Yea, since its likely never been removed I should probably give it a full cleaning and rebuild anyways instead of being lazy! lol

              Comment


              • Spydr
                Spydr commented
                Editing a comment
                I wouldn't say *Lazy*... There Is a lot of crap involved in removing it.

            • #10
              If you want to rejet should get a free flowing filter as well...MI have put
              K&N open round filters (universal 066V) and rejetted 3 Roadstars....work great....and filter is $60
              "I'm Ricky Bobby. If you don't chew Big Red.....then Fuck You"

              Comment


              • Padre
                Padre commented
                Editing a comment
                Do you have a link to these filters? Would I also have to get a small filter for the crankcase breather if switching to one of those?

            • #11
              Just wanted to give an update on what was causing my bike to run lean.

              It turns out the previous owner when removing the AIS had used a machine screw to plug up the vacuum line coming out from the top of the intake manifold. In theory i guess this may have worked but after inspecting my intake and checking around the connections to the heads and not finding any leaks, the lightbulb came on and i realized it must have been leaking just slightly in through the threads of the screws. So yesterday i removed the screw and plugged it with the tip of an old Philips head screwdriver and voila! The bike is now running like a champ, no more popping on decel, no more backfiring when shutting off!

              Cheers!

              Comment


              • Spydr
                Spydr commented
                Editing a comment
                Padre, I've always soldiered mine shut. NO air leak... Period.

              • Padre
                Padre commented
                Editing a comment
                next time I'm in there i will do the same

            Latest Posts

            Collapse

            Topics Statistics Last Post
            Started by Eazy1, 27 minutes ago
            2 responses
            8 views
            0 likes
            Last Post Eazy1
            by Eazy1
             
            Started by Pauli466, 4 weeks ago
            5 responses
            92 views
            0 likes
            Last Post Eazy1
            by Eazy1
             
            Started by Pauli466, 1 day ago
            17 responses
            136 views
            0 likes
            Last Post Pauli466  
            Started by NCB, 3 days ago
            21 responses
            198 views
            0 likes
            Last Post fastjohnny  
            Started by Father Pobasturd, 5 days ago
            45 responses
            278 views
            0 likes
            Last Post tapeit59  
            Started by MCMLXXIV, 07-25-2019, 01:08 PM
            15 responses
            409 views
            0 likes
            Last Post K. Clayton  
            Started by Pauli466, 4 days ago
            12 responses
            171 views
            0 likes
            Last Post Pauli466  
            Started by p birk, 19 hours ago
            2 responses
            66 views
            0 likes
            Last Post Tropicalrs  
            Started by Jaybo, 3 days ago
            5 responses
            186 views
            0 likes
            Last Post Questcap  
            Started by roadiemort, 1 day ago
            10 responses
            103 views
            0 likes
            Last Post Lug Nut
            by Lug Nut
             
            Started by thunderace4, 10-19-2019, 12:34 PM
            28 responses
            403 views
            0 likes
            Last Post thunderace4  
            Started by Herrindude, 1 day ago
            4 responses
            60 views
            0 likes
            Last Post Jclevesque  
            Started by K. Clayton, 4 weeks ago
            10 responses
            237 views
            0 likes
            Last Post K. Clayton  
            Started by cromwell, 3 days ago
            14 responses
            101 views
            0 likes
            Last Post Bikerron  
            Started by Troyf19, 3 days ago
            10 responses
            147 views
            0 likes
            Last Post davej
            by davej
             
            Started by roadiemort, 2 days ago
            19 responses
            31 views
            0 likes
            Last Post roadiemort  
            Started by NCB, 3 days ago
            9 responses
            123 views
            0 likes
            Last Post Questcap  
            Started by Ypsilonn, 02-24-2018, 02:22 AM
            93 responses
            3,667 views
            2 likes
            Last Post Ypsilonn  
            Started by NCB, 3 days ago
            9 responses
            81 views
            0 likes
            Last Post brianmac  
            Started by Pauli466, 4 days ago
            13 responses
            128 views
            0 likes
            Last Post Pauli466  
            Working...
            X