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Homemade CDI ignition

Discussion in 'General Electronics Chat' started by SimonTHK, May 9, 2011.

  1. leftfield95

    leftfield95 Member

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    Look up "Wasted Spark Ignition", although i suspect some manufacturers may call it something different.
     
  2. SimonTHK

    SimonTHK Member

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    ya it must be in series :)
    Thanks
    I might find the problem, I have to test it soon.
     
  3. SimonTHK

    SimonTHK Member

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    OH JESUS MOTHER OF HAPPY MERCY! I figured out the problem :D

    The spark plug wire was broken inside the CDI, it was NOT easy to get in there, but with the right tools it went smooooth (tried with melting and stuff like that). I will put up a complete guide about this problem for my ski :)

    Thanks to everyone who helped me. In the start I knew not much about the electronics. You helped me to get an understanding of it and that made me realise that I could locate the problem to some places quite easily :) and thats what I have done now.

    The most sad thing is, that I now realize that my old bad attitude CDI (which is a tuned more expensive CDI) probably had the same prob :) but that one is for sure dead after I hammered it.

    also I bought a book for my ski, so next time I hopefully know more about the ski itself xD
     
    Last edited: May 15, 2011
  4. dave

    Dave New Member

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  5. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    Didn't I say that was a typical problem a while back?

    The constant vibrations break the wire. If you can rig up a support with something non-metalic.

    A few years ago, I had to replace the coil on a lawn mower for that reason (broken HV wire at the coil).

    I had a car with pop-up head lamps. Turns out that the wires flex and break, so I replced them with super flexible test-lead probe wire.
     
  6. debe

    debe Active Member

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    Simon some pics of the CDI unit would also help.
     
  7. SimonTHK

    SimonTHK Member

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    NOT good pictures I know. But I will ahve better pictures.

    Only the dremel with alot nice tools made this easy, else it was pain in ass to get in there. I just sloooowly moved further and further into the CDI looking out for any coils or any components not to be hurt. I didnt hit any, just 1 big fat piece of metal with no sparkplug on the end. I had no idea it would be that big and easy to find :)

    If anyone said earlier that it was maybe a broken wire, I just didnt know how I could be sure of that or how I could get in there without just destroying the CDI.
     

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    Last edited: May 15, 2011
  8. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    Usually, you wiggle the plug wire while cranking at the coil side.
     
  9. sujith34

    sujith34 New Member

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    It's totally possible with two cylinders.
     
  10. jclaudii

    jclaudii Member

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    That's awesome it was just a break in the wire, but sucks that it was way into the module itself. I guess just get some new spark plug wire and put it on and then reseal it with silicone.
     
  11. Blueteeth

    Blueteeth Well-Known Member

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    I'm afraid I have no experience to contribute anything on this subject. BUT!... I just wanted to post a thankyou, to the thread-starter, and all the posters here. This is why I come here, to learn, read discussions about techie things, and hear peoples experiences. This thread serves as a shining example of contributors helping others understanding how things work, and trying to improve them. Engineering at its finest.

    Blueteeth.
     
  12. mostafa_gordy

    mostafa_gordy New Member

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    hi guys,
    iam sorry for poor English.
    I want to make a programmable cdi Ignition for 4 cylander (spark ignition )automotive engine ( 1.6 Liter) based on www.sportdevices.com circuit.
    my questions is:
    what is change need in the software of PIC Microcontroller?
    whats way to change (replace )magnatic sensor with optical sensor (Piranha or Crane optical sensor )?
    for exapmle CNY70 IR sensor .
    what is change need in the trigger plate of optical sensor(CNY70)?
     
  13. DerStrom8

    DerStrom8 Super Moderator Most Helpful Member

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    Hi mostafa. I would recommend you start your own thread, rather than hijacking someone else's. You can do that by just going to the main page, selecting the forum you want to post to, and click the blue button that says "Create New Thread".

    Regards
     
  14. bountyhunter

    bountyhunter Well-Known Member

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    Here is the CDI that I built for my motorcycle.
     
  15. Jaguarjoe

    Jaguarjoe Member

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  16. DerStrom8

    DerStrom8 Super Moderator Most Helpful Member

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    In case people haven't noticed, this thread is from a year ago....
     
  17. Master scientist

    Master scientist New Member

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    question is...ARE there anyone who have succeeded building their own CDI or DC-CDI with or without advance curve or mapping?

    I am just so curious how a project been started a long time ago, and yet no finished project or updates maybe been posted after.
     
  18. SimonTHK

    SimonTHK Member

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    Hello
    I am the original poster and I did NOT finish the project :)
    The reason why, is cause I just did not know enough electronics (1 year back then now 2 years of study). I did hope that my electronic teachers could help me, but they was not very helpfull and I began another project instead.
    Also small things like wiring a coil got in the way. I hoped that it would be possible to buy those things and that I should only do the circuit board and programming.
    Though now and then it is still in my head :) I know alot more about the ignition system now than I did to begin with.
     
  19. bountyhunter

    bountyhunter Well-Known Member

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    YES. My CDI has no advance built in because it works with the original points and mechanical advancer already in place.
     
    Last edited: Jul 7, 2012
  20. KuTkUtErO

    KuTkUtErO New Member

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  21. DerStrom8

    DerStrom8 Super Moderator Most Helpful Member

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    KuTkUtErO, two things:

    1) Please do not post facebook links here. It gets a bit too personal, and also opens you up to hacking or spam (not by members here, but by outsiders who view the forum).

    2) Please look at Post #92

    Good luck.
    Matt
     

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