Read my spark plug?

Discussion in 'Motorized Bicycle General Discussion' started by Tony01, Sep 26, 2015.

  1. Tony01

    Tony01 Active Member

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    Engine was bogging at high RPM.. I made an adjustment wrong way I guess, THEN started bogging at all rpms, I leaned it a bit and it was better but still bogging at high rpm.

    What does it mean that everything is carbon fouled except for the electrode tip?
     

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  2. crassius

    crassius Well-Known Member

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    my first guess would be too rich with some carbon being blown away to reveal white from previous setting - you might clean it & try again or try a new plug
     
  3. Davezilla

    Davezilla New Member

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    Too rich... the powdery carbon gets blown off by the spark so it won't stay on the electrode tip...
     
  4. FFV8

    FFV8 New Member

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    Too rich.

    You need a fresh plug. While that one still works, and may eventually clear more of that carbon - it will make seeing small changes much harder.

    Install a new plug & ride it a few minutes to warm up. make a WOT pull then pull the clutch in & kill the engine. When it cools down pull the plug & check it.

    It can take hundreds of miles to clear out carbon on an insulator like the plug in your picture. Once you get what you want from the new plug, put that blackened one back in & ride the heck out of it.

    .
     
  5. Davezilla

    Davezilla New Member

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    Fully agreed... anytime you get an over rich read, the only way to get an accurate read the next time is with a new plug. I use the Autolite #275 plugs for tuning since they work good but they're also inexpensive at less than $2 per plug when bought in the 4 pack
     

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