Reading The Plugs

Discussion in '2-Stroke Engines' started by CPC, Apr 17, 2009.

  1. CPC

    CPC Member

    Here is what I found on reading 2-cycle plugs....pic attached....also my plug

    Attached Files:

  2. Pablo

    Pablo Motored Bikes Sponsor

    How many miles on yours?

    How was your shut down procedure prior to pulling?

    It looks well used. The electrode is out of focus so it's a bit difficult to tell, pretty heavy carbon on the walls.
  3. CPC

    CPC Member

    just pulled after changing my needle setting last night, so about 4 miles since then....yes carbonated, but not white or a light grey as shown on the "bad plug" pics. overall this plug has about 150 miles on it though, run at a much richer setting
  4. Mountainman

    Mountainman Active Member

    regarding the looks of your plug

    if I pulled that ((plug thing)) and took a look

    I would say that THINGS seem to be burning pretty darn well

    that's what I would call ((darn close)) to the color my Grandfather always looked for

    especially considering that this is a plug pulled from a two cycle engine -- looks good

    ride that MB thing sideways
    Last edited: Apr 17, 2009
  5. CPC

    CPC Member

    heres another pic

    Attached Files:

  6. CPC

    CPC Member

    GOOD! thats what I was hoping to hear!
  7. Pablo

    Pablo Motored Bikes Sponsor

    Electrode looks good.
  8. CPC

    CPC Member

    So I will recheck it in 25 more miles or so, and see how its looking then, will prolly have the plug sandblasted to clean it throughly first though, so we can see from a fresh start
  9. Mountainman

    Mountainman Active Member

    yes -- good picture

    yes -- good picture of your plug here

    ok -- maybe a little build up noted
    but to remember -- we got a two stroke going on here
    keeping THINGS lubed and burning some oil is normal

    couple of questions -- if you got the time ??

    is the engine new ??

    what mixture of oil in gas are you using ??

    why did you pull the plug -- your MB was running good -- correct ??

    have fun as you ride that -- thing sideways
  10. CPC

    CPC Member

    the engine has around 250 miles on it, im using 20:1 gas/oil mixture, I pulled the plug to read it after changing setting on needle valve
  11. Pablo

    Pablo Motored Bikes Sponsor

    But did you go full throttle on a hot engine, throttle off, then spark OFF, and glide to a stop (no idle)? Cool engine, pull plug.
  12. CPC

    CPC Member

    dont think so except ride @ full throttle
  13. Mountainman

    Mountainman Active Member

    maybe 25-30:1 after break in ???

    seems that for 20:1 -- your plug looks darn good

    when the time comes for a leaner mixture
    there is a thread called -- peferred 2-stroke mixture is ???
    something like that anyway
    it's a poll

    just up top the mountain here
    I keep them always a touch rich -- 25-30:1 after break in period
    some wish to go super super lean -- I don't know why ???

    ride that thing sideways
  14. CPC

    CPC Member

    Just got back from a delivery, WOW runs like a champ now! :) Anyways am having the plug sandblasted tommorow, then we can read the plug from the start. Also, just mixed a freash gallon og 20:1 lastnight, for the next gallon or 5 I think im going to go with 24:1 simply to be on the safe side, then down to 28:1 for another 5 gal, and will prolly not go any leaner, since I do tend to ride wide open, and just cant afford a failure at this point in time.....
  15. CPC

    CPC Member

    I pulled the plug on Forbisher's advice, he's giving me all sorts, and alls been real sound advice! Thanks Forbisher
  16. Ghost0

    Ghost0 Guest

    I agree your fuel/air mixture looks about perfect, might try going to 30:1 on the oil which will reduce the carbon build up. I would not recommend sandblasting your plug though. Has a great potential to do more harm than good. I would just replace the plug after changing your fuel/oil mix.
  17. BSA

    BSA Guest

    Dont forget use the right heat range!!!!!
    Otherwise reading the spark plug is a waste of time.
    NGK B5hs is appropriate for areas with ambient temps below 100 farenheit. Over that use B6HS.

  18. CPC

    CPC Member

    then I need both plugs! I live in a semi desert area, even in the hottest months, it can be 70 when you leave home, and 2 hours later 110, let alone rode temps over 150!
  19. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    NGK B5HS Spark Plug
    use in ambient temperatures of 40 to 80°F.

    NGK B6HS Spark Plug
    use in ambient temperatures of 80 to 110°F +.

    It really isn't that sensitive.....and I live in a similar climate
    I prefer to use the DENSO W20FP-U which is an equivalent of NGK BP6HS

    Caution: They are extended tip plugs that protrude into the combustion chamber
    so check the piston to plug distance

    but they have fit all the 66 cc motors I have seen and SHOULD fit on most 50 cc too
    Last edited: Apr 17, 2009
  20. CPC

    CPC Member

    thats what im using as we speak