Roll Your Own CDI
- Thread starter rohmell
- Start date
Ok well here it goes. I just ordered all of the necessary and suggested components for the "Roll your own CDI" I'll have more than enough pieces as some of the parts I ordered ($.99 w/ free shipping) came with 10-20 pcs. Looks like I can build a few! Also I might have most of the pieces if/when I eventually build the CDI in the "modified cdi and cr 80 coil" thread. Thanks for your help and get ready for some questions!
Yeah I know. I want to sell that racing cdi I just bought and I haven't even received it yet. I suppose I could just put it back on Ebay and see what happens.
rohmell, do you think there's a way to lay this out on some kind of board so i can fit it in a box? or do you think it's best just to use a container such as the pill bottle? sorry for all the questions...
Absolutely you can lay these parts out on a board,
RYOBUSA is working on exactly that in this thread:
http://motorbicycling.com/f13/modified-cdi-cr-80-coil-28853.html
RYOBUSA is working on exactly that in this thread:
http://motorbicycling.com/f13/modified-cdi-cr-80-coil-28853.html
***SUPER CDI!***
16 different overall timing curves, binarily selected, plus a variable timing curve.
16 different retard/advance settings, binarily selected, plus a continuously variable timing adjustment:
Images are of prototype unit. Production unit will have a *real* etched and drilled PCB, target price: $50 USD.
16 different overall timing curves, binarily selected, plus a variable timing curve.
16 different retard/advance settings, binarily selected, plus a continuously variable timing adjustment:
Images are of prototype unit. Production unit will have a *real* etched and drilled PCB, target price: $50 USD.
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The holy grail of Happy Time engine Cdi's!
I am impressed! Will you be producing these or doing a parts list and schematic?
I am impressed! Will you be producing these or doing a parts list and schematic?
No, I found it in the garbage.
Of course, I made it, don't you recognize my favorite 'Big Yeller Caps' ?
I don't need the sarcasm 
Yeah, that sure is a good one. I'd love to see that as a product, people would buy that. I think I speak for a lot of people when I say that I would pay at least $50 for an adjustable cdi box. I'm selling my only HT powered bike though
Yeah, that sure is a good one. I'd love to see that as a product, people would buy that. I think I speak for a lot of people when I say that I would pay at least $50 for an adjustable cdi box. I'm selling my only HT powered bike though I will be producing these, but remember, this is a prototype, and is in the testing stages right now. I might add a thermistor that you can remotely mount to the cylinder head for temperature-controlled timing curves, maybe a little LED that verifies incoming magneto pulses, etc.
What?!? That's awesome! And I just bought components to make my own. What do I need other than these parts to make something similar (if you'll allow me)?
2-1.ouf/850v capacitors
1-c106 4A 400V SCR
18 & 82 ohm 1/2w resistors
3A 1000V diode
2-1.ouf/850v capacitors
1-c106 4A 400V SCR
18 & 82 ohm 1/2w resistors
3A 1000V diode
You need three of the 3A 1000V diodes for the simple CDI.
I suggest first building the simple one, and getting a feel for how it performs. Then you can add to it the components needed to make the Super CDI, which is still in the testing stages. The info for all of that are in these threads. I have not finalized the values for the resistors or the capacitors that are selected via the DIP switch yet, and may want to add more features such as a remote thermistor or maybe an LED.
Due to all of the different ignition coils that are available, I need to do some testing with different coils and see how everything behaves together.
I don't want to try and sell some POS that people are going to have problems with, I want to offer a good, reliable, solid product.
I am putting all this information out here for all to enjoy and learn from, and experiment with, and I hope everyone reading these threads tries their hand at building their own CDI.
I have a ton of extra parts thanks to the bargains on ebay. The only downside is that I have to wait forever.
