Brand new 80cc has spark won't start!

Discussion in 'Welcome to the World of Motorized Bicycles' started by Mr big, Apr 11, 2018.

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Why will it not start?

  1. Not grounded

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  2. Bad fuel air mixure.

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  1. Mr big

    Mr big New Member

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    Hello all! I just bought a new 80cc motor kit. I put it all together on a beach cruiser with no big problems. After making sure everything was aligned and perfect i started it up fir the first time. Within a minute it started and ran. Ran for less than an hour. Then stalled as i let it idle just for break in period. After that i cannot get it to start. I checked all the wiring and carby. Thought it might be flooding so i bent the flanges in bowl of carby and still will not fire. Other than chinese gremlins i am at a loss. Any help would be great!
     
  2. Chaz

    Chaz Active Member

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    Bad news for you I'm afraid. I think you have overheated your engine by letting it idle for so long. These are air cooled and need to have air flowing over the cooling fins of the cylinder and head. Five minutes idling stationary is not good, ten minutes is worse...
     
  3. Mr big

    Mr big New Member

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    Also i live in upstate ny and it was about 35° out and i only let it idle for about 5 minutes.
     
  4. Tyler6357

    Tyler6357 Active Member

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  5. CrazyDan

    CrazyDan Member

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    Believe it or not colder air can make an engine run hotter than warmer air. Cold air has a higher density (more oxygen in a given volume) than warm air and makes the engine run a little lean unless jetting is adjusted... leaner=hotter. Hopefully you didn't cook it... good luck.
     
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  6. Mr big

    Mr big New Member

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    Thanks guys. Just tested for spark and not getting any. Put a drill to crank near magneto. Turned drill on and then tested for spark between blue and black wire and also white and black wire. Doing this should i have seen a spark? Anyway i did not.
     
  7. Tyler6357

    Tyler6357 Active Member

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    To test for spark remove spark plug from head, connect spark plug boot to spark plug, hold the threads of the spark plug to the fins of the head to create a ground, crank the engine with clutch engaged, you should see a spark on your spark plug, do it in the shade or you might not be able to see it good.
     
  8. Mr big

    Mr big New Member

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    I have done this. And no spark. I removed magneto to inspect it and no spark yet. What is the correct wat to put magneto back on? All stock?
     
  9. Mr big

    Mr big New Member

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    I also would like to know if putting an electric drill to bolt near magneto to crank motor to test it is really that harmful to motor or not? Nit sure how it would harm motor?
     
  10. Tyler6357

    Tyler6357 Active Member

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    I don't know if a drill can really damage anything, if it were to damage anything it would probably be the magnet. Anyway, the magneto should be installed in the 1 o'clock position.
     
  11. crassius

    crassius Well-Known Member

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    even with spark plug out, I've had customer strip end of crank with a drill - that nut & threads may be 4.8 like all the other cheap chinese stuff
     
  12. KCvale

    KCvale Well-Known Member

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  13. KCvale

    KCvale Well-Known Member

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