#### leftfield95

##### Member
Is that setup called anything? It seems for me that you connect a plug to both of the HV secondary coil wire ends, and that should work? Or is it simply just 2 secondary coils independent from each others?
Look up "Wasted Spark Ignition", although i suspect some manufacturers may call it something different.

#### SimonTHK

##### Member
ya it must be in series
Thanks
I might find the problem, I have to test it soon.

#### SimonTHK

##### Member
OH JESUS MOTHER OF HAPPY MERCY! I figured out the problem

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

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#### KeepItSimpleStupid

##### Well-Known Member
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.

#### debe

##### Active Member
Simon some pics of the CDI unit would also help.

#### SimonTHK

##### Member
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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#### KeepItSimpleStupid

##### Well-Known Member
Usually, you wiggle the plug wire while cranking at the coil side.

#### sujith34

##### New Member
It's totally possible with two cylinders.

#### jclaudii

##### Member
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.

#### Blueteeth

##### Well-Known Member
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.

#### mostafa_gordy

##### New Member
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)?

#### DerStrom8

##### Super Moderator
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)?
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

#### bountyhunter

##### Well-Known Member
Hello electro people!

I have a jetski, and now something have burned in it twice, something that cost a student 150$each time it happens. With all the great and fantastic help, I am sure I can build this myself. But I need the help A similar jetski: 1991 KAWASAKI 650sx$1,200

The problem on my ski is that it burned the CDI ignition twice. This is kinda like a programable spark plug ignition.
Right now I look at this "guide": SportDevices. CDI Programmable Digital Ignition.
and it is the same picture I have put here with numbers, so its easy for me to ask and you to help.
It is not my idea to use the same microprocessor or follow this guide 100%, I just need to know what it is all about.
Please have in mind that I havtn studied much over a year.

Q1, number 1: Would you build such and ignition coil yourself? Or can it be bought? It has 200-300v primary and 30k v secondary.
Answear:

Q2: The guide is for one spark plug, my machine have two. I guess I could use the same ignition coil for both spark plugs, I just have to lead the current with a mosfet or what would you use?

Q3, number 6: I know that an ignition coil makes the spark plug spark when it discharges right? How does it disharge in this schematic? Through the thyristor? When RA2 (number 2) is high?

Q4: In this circuit the microprocessor should register the "pick up" pulse, have a delay time programmed and then make an output to the thyristor. Can anyone confirm this?

Q5, number 2: There are shown 2 diodes with a resistor. The right side is from the Uc to send an ignition signal right? What is the left side doing? I cant figure that out?

Here is the CDI that I built for my motorcycle.

#### DerStrom8

##### Super Moderator
In case people haven't noticed, this thread is from a year ago....

#### Master scientist

##### New Member
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.

#### SimonTHK

##### Member
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.

#### bountyhunter

##### Well-Known Member
question is...ARE there anyone who have succeeded building their own CDI or DC-CDI with or without advance curve or mapping?
YES. My CDI has no advance built in because it works with the original points and mechanical advancer already in place.

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#### DerStrom8

##### Super Moderator
hi to all i am new here need help about my cdi my motorcycle is honda hawkmatic which have to cylinder.. here is the picture https://www.facebook.com/dodogkid/media_set?set=a.4823263314512.1073741830.1684370093&type=3 can someone here help me up to build a relacement like this..

maybe u can help me guys by "DIY" for giving me a schematic diagram and parts list that i needed

thank u all
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