Discussion in '2-Stroke Engines' started by sharky80, Feb 2, 2015.

  1. sharky80

    sharky80 New Member

    Why do I already have to change my spark plug, I haven't even put 1hour on my new 80cc engine. What's causing this?

  2. cmb271

    cmb271 Member

    can you give some more detail, why do you have to replace it, have you tested the old one, whats your mixture you're running, are you properly breaking it in?
  3. sharky80

    sharky80 New Member

    I ran with no load for an hour. Took for a 1 mile test. Then a 2 mile test. Started 2 more times fine .then 1 hard start. Then no start.I replaced the plug today.still no start.16.1 mix for break in. Now I have strong spark.I tryed adjusting float a little no difference. Inspected magneto and cylinder visually. What next?
  4. butre

    butre Well-Known Member

    why did you run no load for an hour? if that was the first time running it, you've glazed the hell out of the cylinder walls
  5. KCvale

    KCvale Motorized Bicycle Vendor

    16:1 is too much oil in the gas.
    25:1 is good for a tank of RPM varying riding (even WOT for brief times) for break in, then you can go to 32:1 synthetic.

    2-strokes don't like idle, they are happy around 5500-6500 RPM under load.

    To get started agin try pulling the plug and with the gas off and the clutch out ride it up the street and back to blow out any puddled fuel in the crankcase, insure your head bolts are torqued in an alternating pattern to 20# and you that may fix you up.

    Also, the stock plugs are crap, try an NGK 5944 (BPR7HIX) Iridium plug, you'll thank me for that tip ;-}
    sharky80 likes this.
  6. sharky80

    sharky80 New Member

    I dig what you suggested. I'm still not getting any run. I have spark with plug out of the cylinder. I drained fuel and put in 25.1 blew out the cylinder like you said. Still no run.I'm having a hard time finding that NGK plug Please
  7. darwin

    darwin Well-Known Member

  8. sharky80

    sharky80 New Member

    I have a feeling I'm not getting spark while S plug in in cylinder.
  9. darwin

    darwin Well-Known Member

    Do you have a kill switch on the bike hooked up? If so unhook it and see wassup. When you try to start it and it won't start what does the plug look like when pulled? Is it wet? When you check the spark with the plug out is it a nice strong blue spark or yellowish?
  10. birdmannn101

    birdmannn101 Member

  11. sharky80

    sharky80 New Member

    Yes I will try disconnecting kill switch. The plug is coming out wet.and has a strong blue spark out of the cylinder. I'll try the kill switch.thanks
  12. KCvale

    KCvale Motorized Bicycle Vendor

    If you are getting good spark out of the cylinder it is not the kill button.

    That leaves ignition timing, fuel and compression.
  13. sharky80

    sharky80 New Member

    OK what should I do? The plug is wet.compression feels good. The mother is new what should I check next? Thanks for the input.