125cc Moped Won't Start No Spark

Discussion in 'General Scooter Discussion' started by gamecelt, Jul 21, 2019.

  1. gamecelt

    gamecelt Member

    Messages:
    52
    I have bought a project 4 stroke 125cc Direct Bikes Scorpion Moped. Turns over but won't start. I initially took the carb off and gave it a good clean. Still wouldn't start.

    Then I checked if there was spark by taking the spark plug out and then doing the normal test touching it to frame and turning it over to see if there was a spark.

    There is no spark.

    Any ideas?
     
  2. Stevep

    Stevep Well-Known Member

    Messages:
    5,698
    Could be any number of things from the pick-up on the flywheel, the flywheel itself, broken wire, knackered cdi, coil lead, plug, cap......
    Start at the cheapest end and work your way along
     
  3. gamecelt

    gamecelt Member

    Messages:
    52
    I have ordered ignition coil, cdi and stator coil. I'll try those first they were just under £30 for all 3 so not bad.

    When I first start it there is a spark for about a second then nothing. If I leave it for a few hour there is a spark again for a second then nothing. That is when testing it on a ground ie the frame.
     
  4. scubabiker

    scubabiker NITROJUNKIE

    Messages:
    7,321
    Sounds a bit like a coil fault to me
     
  5. Stevep

    Stevep Well-Known Member

    Messages:
    5,698
    Bad earth point maybe?
    Or dirty pip on the flywheel and pick-up
     
  6. gamecelt

    gamecelt Member

    Messages:
    52
    Right.

    1. I changed the ignition coil. Again a few sparks and then nothing.
    2. The cdi unit that came was 6 pin but smaller than the one on the bike (does that matter)?
    3. Then I took the flywheel cover off and the magneto was covered in oil (see photos before I cleaned it compared to new one not yet fitted).

    Still won't start. So tomorrow I will change the stator when my stator tool comes.

    4. However just for the fun of it I checked the compression it was on 50 to 60 psi (See photo). Any ideas?

    5. Oh and the wiring of the stator on the bike has been slightly adapted when comparing it to the new one.
     

    Attached Files:

  7. Karmafield

    Karmafield Member

    Messages:
    67
    Couldn't the flywheel have de-magnetized? Honestly I HAVE NO IDEA why that thought popped into my mind. Or is it even a thing... Just check it for safety. It should be pretty strong when put a metal washer besides it. Also, I recommend to check for bad grounds, eliminating the wires one by one.
     
    Last edited: Jul 23, 2019
  8. scubabiker

    scubabiker NITROJUNKIE

    Messages:
    7,321
    60 psi is not enough..
     
    MARSH likes this.
  9. Stevep

    Stevep Well-Known Member

    Messages:
    5,698
    More than a few things going on here then.....
    ^^^as said above, no where near good enough. Should be 130psi or above for a 125.
    Go online, order a new piston and barrel kit with gaskets, you'd be surprised how cheap they are really.
    While you're waiting for those to arrive, clean the flywheel and pick-up points, charge the battery, clean the earth points all round, especially to the engine and frame, change the plug for a new one, try the spark again.
    If no joy, wait for the new stator and pick-up.
     
    MARSH likes this.
  10. gamecelt

    gamecelt Member

    Messages:
    52
    Okay guys got it working and it runs like a dream.

    It was the stator. As mentioned above I replace the ignition coil and cdi but no joy. So ordered a stator. Took the flywheel off and got to the stator it was filled with gunge, oil and grass (see photo I have uploaded). I cleaned out the casing which it sits on and put a new stator in. Tested the spark it was great. Put everything back together it started up no problem at all. So not sure why I got the 60 psi reading but it now has no problem starting.

    Thanks for your input.
     

    Attached Files:

  11. Stevep

    Stevep Well-Known Member

    Messages:
    5,698
    More than likely you didn't screw the tester in all the way to create a good seal.
    I've done it myself. It's the little 'o' ring that splits on the tester adapter and you dont notice.
    However the good thing is that it is working now so BRAVO:)
     

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