So, I've got an old flyback transformer from an RPTV - I agree, we gotta try it out. I'm still hunting locally for a pot that can handle high voltage and/or an SCR. Smallest I have that's high tolerance is 1500V 8A, and I dunno about that one.
Roll Your Own CDI
- Thread starter rohmell
- Start date
Dang I knew I should have stayed away from this thread, I just might have enough fork lift parts in my tool box at work to try this. My wife allready says I spend too much time in my shop
What kind of voltage rating on those forklift SCRs? They might have a too low voltage rating
I don't remember the voltage ratings on the recs, that one thing I'll have to check Tuesday. I have the caps and most of the other thing here at home. It just got me thinking of what I had and what it would take to make a better cdi. I have a rt180 yamaha coil that is still good, it may work for this.
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Here's another, but they mixed up the K and G:
Electronic Motocycle ignition CDI Honda C-90 | Circuit Project Electronic
Electronic Motocycle ignition CDI Honda C-90 | Circuit Project Electronic
Voltage is going to be a factor, the only parts I have found that may work are rated 480v a/c. R/M were you talking about a/c or d/c rating.
can you use a stock cdi and rework it? rohmell how much you looking to get shoot me a pm I have the perfect coil for that cdi.
If you can get the potting compound out of the stock CDI, it can be reworked.
Try MEK or DMSO to see if the potting material can be removed.
Would one just soak the CDI box in the solvent for a day or two to soften it?
Can the solvent damage any of the components, IE penetrate inside them or damage the coating on the resistors, capacitors, coil and whatnot rendering them unreadable?
The only think I have dug out potting from was a dead Harley Davidson voltage regulator.
They used black RTV silicone. I was not successful in saving the circuit components as the silicone was murder to pick and scrape out.
Can the solvent damage any of the components, IE penetrate inside them or damage the coating on the resistors, capacitors, coil and whatnot rendering them unreadable?
The only think I have dug out potting from was a dead Harley Davidson voltage regulator.
They used black RTV silicone. I was not successful in saving the circuit components as the silicone was murder to pick and scrape out.
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Those solvents can wreak havoc with most components. Even if the resistors and capacitors' markings are gone, they can still be measured with test equipment.
We know the basic schematics of these devices, so it is not a problem to recreate a CDI circuit that would work, but it would be interesting to know what specific components and values are used in the Chinese Kit CDI.
We know the basic schematics of these devices, so it is not a problem to recreate a CDI circuit that would work, but it would be interesting to know what specific components and values are used in the Chinese Kit CDI.
You Can Never Have Too Many SCRs
Here's a lot of 25 SCRs, you can never have too many SCRs, this is good for those thinking of building some of these units and perhaps selling to others:
25 PCS GE C106D1 C106D 400V 4A SCR RECTIFIER DIODE BOX7 | eBay
Here's a lot of 25 SCRs, you can never have too many SCRs, this is good for those thinking of building some of these units and perhaps selling to others:
25 PCS GE C106D1 C106D 400V 4A SCR RECTIFIER DIODE BOX7 | eBay
Here are some SCRs that are a wee dab beefier:
(10) Teccor SCR S4025L 400V 25 Amp Semiconductor | eBay
(10) Teccor SCR S4025L 400V 25 Amp Semiconductor | eBay
I once worked for a semiconductor manufacturer, and those SCRs were test units and samples.it's pretty hard to find scr's for cheap. Where did you get those scrs with the threaded shafts rohmell? those look like they would dissipate heat a little better
These SCRs are cheap, and you get 25 pcs, they are the same as those used by other CDIs that have been mentioned in this forum:
http://cgi.ebay.com/25-PCS-GE-C106D...949?pt=LH_DefaultDomain_0&hash=item5d2ebc397d
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Actually, you don't need such a heavy-duty industrial-strength SCR.
400, 600, 800 volts is fine, I scoped my CDI at around 318-320 volts peak.
Other CDI circuits floating around all seem to be using a 400V 4A SCR, so you don't need some huge SCR rated at 50, 40, 20A, or whatever.
400, 600, 800 volts is fine, I scoped my CDI at around 318-320 volts peak.
Other CDI circuits floating around all seem to be using a 400V 4A SCR, so you don't need some huge SCR rated at 50, 40, 20A, or whatever.