spark plug color

Discussion in 'Engine, Fuel and Exhaust' started by gunnut, Mar 11, 2012.

  1. gunnut

    gunnut Junior Member

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    here we go,sorry if this is the wrong place to post,but,hows my plugs for color,left to rite,front cylinder-rear one.Is my mixture ok,or a little on the lean side?bike runs fine as is.A few tips on what the different colorations mean would be good too! Many thanks guys.
     

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  2. BUBBIE

    BUBBIE Well-Known Member

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    To ME and My way of thinking;

    The one on the left is showing a Richer than need amount of gas. The one on the right MAY tell me rich and maybe a little soot deposit from Oil burning.

    I like the older bikes to show a Light Tan and NO black..
    How dark are the muffler ends? IF black normal but IF sooty Black, Too much Fuel (rich) and or Oil getting burned.

    Does your bike Use any amount of oil that you notice?

    The plugs look too well used.:D

    Might think about NEW set OF Stock HD ones.
    Could make a world of good in the runability of your bike.

    As fin would say "use a little copper grease on the threads" when you install the new ones.

    In the USA, Plugs for harleys are about the best buy Yet.. Under 5$ US for 6R12's set and that is from the Harley Dealer..

    SHhhhhh don't let them know they are considered Cheap here in the US or they will Raise the $$$$.

    signed....BUBBIE
     
  3. R_W_B

    R_W_B Senior Member

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    Excellent advice by Lonnie, and even with EFI you can still read "some" of what's happening on plugs. But just like Glider always said, with EFI, there are variables that make plug reading less exact a science than back in the days when we used to check if we still yet needed a larger metering jet for the carb after a pipe change.
     
  4. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    I agree with the above post, I too would like to see a more tan color on the ceramic insolator. You did not state how long the plugs have been in use and what gap you are running. You also need to be sure that you have the bike running at speed (50 to 60mph) chop the throttle, pull in the clutch and shut off the ignition. As soon as the bike is on the jiffy stand pull the plugs. This is the most accurate way to see how the plugs and fuel mixture are when running.
     
  5. Dr. Dolittle

    Dr. Dolittle Experienced Member Staff Member Moderator Contributor

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    Never heard that before but it makes sense. Just make sure you pull over in a safe area when you stop to check the plugs like this. Shoulder of a busy road might not be a great idea.
     
  6. mat 60

    mat 60 Senior Member

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    Better listen to HDDon...That.s the way we checked our plugs in racing and in snowmobiles..OH No...I said a bad word...Snow...:)
     
  7. BUBBIE

    BUBBIE Well-Known Member

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    That ought to teach you a lesson mat 60.... NO Nasty words allowed here
    Now get out there and Ride...:s

    signed....BUBBIE
     
  8. mat 60

    mat 60 Senior Member

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    Thanks BUBBLE....I appreciate the help..:)..I will get on my bike soon....Mabe It will help me with my nasty language..
     
  9. dbmg

    dbmg Experienced Member

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    No Mat you will have to move......:rofl
     
  10. mat 60

    mat 60 Senior Member

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    QUOTE...MAT....Thanks....:p...I do like it up here but....:bigsmiley30:.OH>>>>My plugs are clean..