Muffler discoloration

Discussion in 'Motorized Bicycle General Discussion' started by FlyingHorse87, Jun 30, 2010.

  1. FlyingHorse87

    FlyingHorse87 New Member

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    I'm breaking in my engine and the chrome muffler is discoloring or "blueing". I know from motorcycling that exhaust blueing means the engine is running too rich, but is it running rich from the 16:1 petrol/oil mix or does the carb need adjusting? My idle screw is about 4 turns out, the side is about 1/8" from the bottom of the carb body. Could it just be the cheap chrome plating burning off?
     
  2. nidyanazo

    nidyanazo New Member

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    The change in color is normal.
    To see if it's running rich, do a plug chop.
    That's where you run the bike at full throttle (or part throttle, whatever rpm range you want to check) and then kill the motor.
    Pull the plug and check if it's dark and wet (rich), white and burnt (lean), or just right with a nice brown tint/
     
    #2 nidyanazo, Jul 1, 2010
    Last edited: Jul 1, 2010
  3. Goat Herder

    Goat Herder Gutter Rider

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    If you are talking about a China 2 smoke? That screw on the side is for idle adjustment. It will not change you air to fuel. You can move the clip up and down on the needle valve.
     
    #3 Goat Herder, Jul 1, 2010
    Last edited: Jul 1, 2010
  4. BarelyAWake

    BarelyAWake New Member

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    Good advice - 'cep ya wanna let the motor cool down before trying to remove the spark plug as you may pull the threads out of a hot motor ;)
     
  5. FlyingHorse87

    FlyingHorse87 New Member

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    Thanks everybody, my plug isn't soaked so it's running fine.
     
  6. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Use 24:1 for the break in!! 16:1 is too much oil!
    & "yes", 16:1 will cause it to run leaner.. More oil = less gas in every drop that goes through the carb & into the engine! ;)
     
  7. kicking

    kicking New Member

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    I see a lot of that blue discoloration f/h ... I was thinking about red or black muffler paint.
     
  8. Kevlarr

    Kevlarr New Member

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    When I took my muffler apart I noticed that the area that turns blue is just past where the catalytic converter is so I'm thinking it more the heat from that then anything.
     
  9. kicking

    kicking New Member

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    yep its more than likely from heat ,,, thats why if I paint mine it will be ,,, im thinking about white ,,,it has got to be muffler paint though to stand up to the heat ,, i painted the manifold and tail pipe on my van with some i bought from carquest because of rust,,,, looks good!
     
  10. FlyingHorse87

    FlyingHorse87 New Member

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    Yes, I need to cut the mixture back. The instructions stated to run 16:1 for the first two tanks! That seemed like way too much oil, it drips and smokes like crazy.
     

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