Converting 5 pin AC CDI to 4 Pin DC CDI any good?

Discussion in 'Ask the Tech Masters???' started by chamjiee, Dec 29, 2017.

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  1. Dec 29, 2017 #1

    chamjiee

    chamjiee

    chamjiee

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    Hi
    Oorcacing is selling 4 pin dc cdi and they have a video about how to convert 5 pin ac cdi to 4 pin dc cdi. Is it any good?

    anyone done it.

    Any performance gain or improvements?

    Also can we use same spark plugs and the ignition coil with this cdi? Or does dc cdi require different ignition coils?


    Regards


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  2. Jan 1, 2018 #2

    rotn50

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    The coil and plug will be fine. My understanding is that ac. requires a battery to run where as dc current is supplied by the magneto. Is there reason for doing this to eliminate a flat battery, or what was there reasoning for doing this?

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  3. Jan 3, 2018 #3

    CookieMonster

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    Pretty sure ac is supplied from the magneto, hence why you need a voltage rectifier to use a battery. Battery supplies and requires dc. Most motors don’t have a battery to begin with unless it’s an electric start motor.
    As mentioned, coils and plugs are fine.
    If you don’t already have a battery circuit, you will likely need to instal a voltage rectifier to get proper dc voltage.


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  4. Jan 3, 2018 #4

    chamjiee

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    I do have battery and rectifier. Firstly I wanted to make sure that existing coil and cdi can be used. Secondly and most importantly I wanted to know if it's any better then ac cdi system?

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  5. Jan 4, 2018 #5

    chamjiee

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    Can someone help me wire it up?


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  6. Jan 4, 2018 #6

    rotn50

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    You are correct mate. Brain fade lol

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    Last edited: Jan 4, 2018
  7. Jan 6, 2018 #7

    chamjiee

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    As mentioned I do have battery and rectifier already installed and working.

    Can I have the wiring diagram?

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  8. Jan 8, 2018 #8

    rotn50

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    I'd just purchase the appropriate harness for the cdi mate. Other then that you will need to Google the diagram.

    If it ain't broke, break it.
     
  9. Jan 8, 2018 #9

    chamjiee

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    I Googleed and wired this cdi and bikes starts.
    However how can I use a kill switch with it.


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  10. Jan 16, 2018 #10

    rotn50

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    You could run a wire off the pickup wire from the cdi as the positive to the black and white wire on the killswitch and then earth the green wire from the killswitch to the frame.

    If it ain't broke, break it.
     
  11. Jan 16, 2018 #11

    chamjiee

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    So that means to stop engine the pulser coil output should be grounded via kill switch button?

    Won't that cause sparking etc? As we are dumping the current from the pulser to ground.

    Also I searched few pinout pics of 4 pin cdi and they say switched 12v what does that mean?

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  12. Jan 22, 2018 #12

    rotn50

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    The black with white stripe killswitch wire will need to be joined to the black with yellow stripe wire for the coil positive. Then just run the green wire to the other greens or earth on the frame or engine. Without worrying to much about the black with red stripe get a multimeter and put it on the battery terminals to see if the battery is charging. If it is charging it will fluctuate between 13 volts and 15 volts.

    If it ain't broke, break it.
     
  13. Jan 22, 2018 #13

    rotn50

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    As this pic here shows blue with white in a 4 pin is the main wire to join to your killswitch but you can also use the black with yellow stripe. [​IMG]

    If it ain't broke, break it.
     
  14. Jan 23, 2018 #14

    chamjiee

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    Got it. This picture explains it.

    So there are three variations of kill switch. Either insert kill switch inline with the 12v feed to cdi, or ground the pulse coil output ( which is hardly 2 volts I think) or ground the Input to the coil (200 volts ac).


    I am a bit skeptical in inserting the kill switch inline to the input of the coil as the Input voltage to the coil are 200 volts so don't want to switch on/off across 200 volts...

    Just curious we are dumping the current from the pulser coil to the ground which essentially causes the engine to cease won't it cause any problem to the pulse coil?

    Many diagrams I see online for dc cdi shows the 12v feed to cdi as switched 12v so I assume that's much good and safe route as we are just disconting the power rather then dumping it.



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  15. Jan 24, 2018 #15

    rotn50

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    It's very common to hook the killswitch up to stop the motor thru the stator pickup mate. Won't hurt anything.

    If it ain't broke, break it.
     
  16. Jan 24, 2018 #16

    chamjiee

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    Thanks will do it. And update of I see Amy improvements in using dc instead of ac

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