Announcement

Collapse
No announcement yet.

Pilot screw

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

  • Pilot screw

    Hi guys can anyone tell me how many turns out the pilot screw should be out on a UK model

  • #2
    I had a set of UK carbs on mine and it ran well at 2.25 turns out. But I don't know whether the factory setting is the same as for the US model (1.5 turns).
    "You don't get slower with age, you just get more cautious." Michael Rutter

    06 Ocean Blue ZZR1200, the coolest colour.
    99 Yamaha R1

    Comment


    • #3
      Yeah the book states 1.5 turns out but mine was set at 2.5 when I took them out just wanted to check I have put them back at 2.5

      Comment


      • #4
        Originally posted by Bigsteve13 View Post
        Yeah the book states 1.5 turns out but mine was set at 2.5 when I took them out just wanted to check I have put them back at 2.5
        2.5 works just fine. Later you can read your plugs just to make sure the mixture is right for your bike.
        Good tuning! Never Surrender.
        Sin's a good mans brother.

        Comment


        • #5
          Hi guys the bike is running but idle is up and down all over the place when I rev it she's is good but when it's coming down it slows about 3k rpm then over a good few seconds she drops nearly stalls but cones back up also when I put the choke on it doesn't do anything there's no change to the rpm the spark plugs are a black sooty...... any help would be very much appreciated

          Comment


          • #6
            As I recall reading some shadetree diagnostics based on how an engine returned to idle, I googled "rich lean idle drops fast slow" and found that this seems to be the general consensus:

            The mixture is lean if:
            the bike surges while holding a steady throttle at about 4000 rpm under a light load.
            there is excessive back-firing on closed-throttle while under load.
            the throttle is lightly 'blipped' and the idle speed 'hangs up' before dropping to the set idle speed.

            Correction action: turn the pilot screws OUT 1/2 turn or so. If the pilot screws end up turned out very much more than three and one half turns total, you should use larger pilot jets. (Or shim the needles.)

            The mixture is rich if:
            the plugs are excessively soot-ed up or fouled.
            the throttle is lightly 'blipped' and the idle speed drops below the set idle speed before rising up to the set speed.
            Correction action: turn pilot screws IN 1/2 turn.
            "Here's to our men in uniform. ALL uniforms." Maximus
            "If you can't get it done on a ZZR1200, you can't get it done on a 14 either." CrazyTrain
            "If the space shuttle didn't keep exploding it would be a pretty good space ship." helodoc
            "Re: Turbo-Connie: It had to be done...
            Like putting a solid-fuel rocket booster on a wheelchair." Danno

            Comment


            • #7
              Just to let you know I turned the pilot screws in by half a turn and she's running great

              Comment


              • #8
                Good deal.

                Glad it was a simple fix.
                I have neither the time,or the inclination, to explain myself to a man, who rises and sleep under the blanket of the very freedom that I provide, and then questions the manner, in which I provide it. I'd rather you just say 'thank you' and go on your way.

                Comment

                Working...
                X