Build a Performance CDI
- Thread starter k.mah
- Start date
Can't bloody wait!
PS, notice how some circuit boards are printed like the game 'battleship'?
That could be utilized, ie; put negative electrolytic capacitor lead in hole 'c-12' and positive lead in hole 'c-14'.
Just a thought; if they weren't printed like that, a fine point Sharpie could do it.
PS, notice how some circuit boards are printed like the game 'battleship'?
That could be utilized, ie; put negative electrolytic capacitor lead in hole 'c-12' and positive lead in hole 'c-14'.
Just a thought; if they weren't printed like that, a fine point Sharpie could do it.
That's actually the plan! Make it very easy to understand. I had no idea not long ago then Ivan H was so kind as to explain everything and give me schematics, plus explain everything! Ivan H gets all the credit for this thread! I'm simply piecing it together 
Re: Waterproofing a mag?
Hi again. I thought that, while at the start of this thread, it may be an idea to post some soldering tips for people who are not expereanced in this, as ur soldering can mean the difference between a CDI that works or doesnt. Ok, u will need a soldering iron (also a stand for the iron when not in use &something to clean the tip of the iron with), some resin cored solder & a small pair of sharp side cutters. For an iron, a 20 watt iron will do the job. Avoid the trigger feed soldering gun types, they are far to clumsy & inaccurate for this, as u will have to do some fine soldering around the jumpers etc. A nice fine chisel or needle type tip will b good. For solder u will want a hobby pack of 1.0mm (diameter), 60/40 resin cored solder. This means it is 60% tin & 40% lead. It must be resin cored. Acid cored, while it will "take" to the job to be soldered will not do, as the acid will later continue to etch the parts u have soldered resulting in really bad electical joins. U will also need something to constantly clean the tip of the iron with. I use a small ashtray full of stainless steel wool, tho a moistened sponge is also fine. Ok, now we get to soldering. There r only a few things to know to do this well. Let the iron heat up to temp. Now it must be cleaned & tinned. Wipe the tip all over quickly on ur chosen cleaner, then touch the end of the solder wire to it. The resin cores, which act as a wetting agent will melt first & flow over the tip lifting any residual gunk, then the solder will melt. It all happens in a second. Melt enough solder onto the tip to evenly coat the little end tip u will be using, then flick off any excess to leave the tip all shiny silver with no solder globs hanging off it. This light coating on the tip is needed for the iron to b able to transfer heat to the component u r soldering & the copper foil track on the board that it is being soldered to. The heat must be transfered to both of these at the same time. So,,, with ur component mounted on the board & with the protuding component legs slightly bent to hold it in place, take ur freshly cleaned & tinned iron & place it on the copper foil track with the tip of the iron also up against the leg of the component. Now introduce the end of the solder wire to the junction of the iron, copper foil & component leg. Feed in just enough solder to form a small pool that encircles & wicks up the leg of the component a little, then remove the iron. Its all over in a second or two. The solder joint should be small & neat, but most of all it should have a shiny silver appearance & have wicked into the surface of both the component leg & the copper foil track . If it has a dull grey appearance it is most likely wot is called a "dry joint" which, while providing an ok mechanical join is providing an unsatisfactory electrical join that will further oxidize & get worse. This tpe of joint must be redone. Also, the juction of the solder pool & the copper foil track/component leg should be like a small even gradient. If where the solder meets either of these 2 looks like a bubble sitting against it the solder has not properly wicked into it & it must be redone. If its good, take ur side cutters & cut the component leg of flush with the top of the solder pool. If u have a few components mounted in their correct position on ur board u can quickly solder up several joins before the iron becomes dirty & needs cleaning & tinning again, however, whenever the iron sits unused for a minute or 2 it will need to be cleaned & tinned b4 using it to solder. When the iron is not being used but is still turned on, leave it in its stand which will usually look kinda like a spring. Touch the tip of the iron agaist this spring so it acts as a heatsink & prevents the iron from burning. So, just to recap,,, the iron must always be clean & always be tinned for successful soldering. The components being soldered must also b clean & free of grease etc. When soldering, it will only take a split second for small components to be heated by the iron, so after touching the iron to the job, quickly feed the solder in, then as soon as the solder wicks into the job, remove the iron. If its shiny siver & looks uniformly even ur all done. If u search U tube u will find soldering guides so u can get a visual of a good joint. It wont take u long at all to be soldering really well if u remember these few simple basics Cheers
Hi again. I thought that, while at the start of this thread, it may be an idea to post some soldering tips for people who are not expereanced in this, as ur soldering can mean the difference between a CDI that works or doesnt. Ok, u will need a soldering iron (also a stand for the iron when not in use &something to clean the tip of the iron with), some resin cored solder & a small pair of sharp side cutters. For an iron, a 20 watt iron will do the job. Avoid the trigger feed soldering gun types, they are far to clumsy & inaccurate for this, as u will have to do some fine soldering around the jumpers etc. A nice fine chisel or needle type tip will b good. For solder u will want a hobby pack of 1.0mm (diameter), 60/40 resin cored solder. This means it is 60% tin & 40% lead. It must be resin cored. Acid cored, while it will "take" to the job to be soldered will not do, as the acid will later continue to etch the parts u have soldered resulting in really bad electical joins. U will also need something to constantly clean the tip of the iron with. I use a small ashtray full of stainless steel wool, tho a moistened sponge is also fine. Ok, now we get to soldering. There r only a few things to know to do this well. Let the iron heat up to temp. Now it must be cleaned & tinned. Wipe the tip all over quickly on ur chosen cleaner, then touch the end of the solder wire to it. The resin cores, which act as a wetting agent will melt first & flow over the tip lifting any residual gunk, then the solder will melt. It all happens in a second. Melt enough solder onto the tip to evenly coat the little end tip u will be using, then flick off any excess to leave the tip all shiny silver with no solder globs hanging off it. This light coating on the tip is needed for the iron to b able to transfer heat to the component u r soldering & the copper foil track on the board that it is being soldered to. The heat must be transfered to both of these at the same time. So,,, with ur component mounted on the board & with the protuding component legs slightly bent to hold it in place, take ur freshly cleaned & tinned iron & place it on the copper foil track with the tip of the iron also up against the leg of the component. Now introduce the end of the solder wire to the junction of the iron, copper foil & component leg. Feed in just enough solder to form a small pool that encircles & wicks up the leg of the component a little, then remove the iron. Its all over in a second or two. The solder joint should be small & neat, but most of all it should have a shiny silver appearance & have wicked into the surface of both the component leg & the copper foil track . If it has a dull grey appearance it is most likely wot is called a "dry joint" which, while providing an ok mechanical join is providing an unsatisfactory electrical join that will further oxidize & get worse. This tpe of joint must be redone. Also, the juction of the solder pool & the copper foil track/component leg should be like a small even gradient. If where the solder meets either of these 2 looks like a bubble sitting against it the solder has not properly wicked into it & it must be redone. If its good, take ur side cutters & cut the component leg of flush with the top of the solder pool. If u have a few components mounted in their correct position on ur board u can quickly solder up several joins before the iron becomes dirty & needs cleaning & tinning again, however, whenever the iron sits unused for a minute or 2 it will need to be cleaned & tinned b4 using it to solder. When the iron is not being used but is still turned on, leave it in its stand which will usually look kinda like a spring. Touch the tip of the iron agaist this spring so it acts as a heatsink & prevents the iron from burning. So, just to recap,,, the iron must always be clean & always be tinned for successful soldering. The components being soldered must also b clean & free of grease etc. When soldering, it will only take a split second for small components to be heated by the iron, so after touching the iron to the job, quickly feed the solder in, then as soon as the solder wicks into the job, remove the iron. If its shiny siver & looks uniformly even ur all done. If u search U tube u will find soldering guides so u can get a visual of a good joint. It wont take u long at all to be soldering really well if u remember these few simple basics Cheers
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Hi, I do not have the ability to draw up the schematic or layout on a computer & post them (totally computer illiterate) however I would like to see them up here to help anyone who wishes to build their own CDI accomplish this. They really are simple to build. If anyone out there does have the ability to draw up the schematic & layout on a computer & wishes to help, give me a yell & I can get a hand drawn schematic & layout for 1 built on vero board to you, either by photographing them & emailling them or by sending thru the post. Again, I can supply a hand drawn schematic as well as a hand drawn layout showing each components position on the board & the foil tracks daigram for the underside of the board. All that will be needed is for someone to redraw onto computer & post here. Cheers
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Hi, as u know I have been trying to get the schematic & a simple vero board layout up here on the forum for some time & being computer illiterate makes this difficult.
Sooo, I have drawn up a largish schematic for the stock aftermarket CDI that people have been able to buy (expensively), as well ad a component layout. I've done it showing the Vero board hole spacing, copper foil tracks shown in orange highlighter, resistors (with values shown) shown in blue highlighter & capacitors (with values shown) shown in yellow highlighter. All wiring connections are also shown. All components are laid out exactly as they are positioned on the board, thetr is absolutely NO chance off getting ANYTHING wrong if using this layout.
So now I will photograph both schematic & layout & tomorrow or the next day, get them to a friend to put on photobucket then post them on this forum. I'll most likely put them at the begining of a new thread. I'll post a complete list of components, aling with recommemdations on which sort to use, quality, tolerance & that sort of thing, also constructiom tips & then, for the adventurous I'll go into simple modifications to adjust every parameter of the intire timing curve including advancing or retarding the initial firing point (& with it the whole curve), making the Hi RPM retard curvr steeper or shallower & moving the point at which it starts to retard either higher or lower in the RPM range. This is only recommended if u are absolutely certain u can accurately diagnos an over advanced condition anywhere in the entire RPM range, as such a condition can quite easilly cause engine damage &/or failure.
So, until they're posted in a day or 2, dont buy an aftermarket CDI. Basic soldering skills can be learned in minutes & even if u know nothing about electronics u'll have no problem at all building a CDI from this layout. Cheers
Sooo, I have drawn up a largish schematic for the stock aftermarket CDI that people have been able to buy (expensively), as well ad a component layout. I've done it showing the Vero board hole spacing, copper foil tracks shown in orange highlighter, resistors (with values shown) shown in blue highlighter & capacitors (with values shown) shown in yellow highlighter. All wiring connections are also shown. All components are laid out exactly as they are positioned on the board, thetr is absolutely NO chance off getting ANYTHING wrong if using this layout.
So now I will photograph both schematic & layout & tomorrow or the next day, get them to a friend to put on photobucket then post them on this forum. I'll most likely put them at the begining of a new thread. I'll post a complete list of components, aling with recommemdations on which sort to use, quality, tolerance & that sort of thing, also constructiom tips & then, for the adventurous I'll go into simple modifications to adjust every parameter of the intire timing curve including advancing or retarding the initial firing point (& with it the whole curve), making the Hi RPM retard curvr steeper or shallower & moving the point at which it starts to retard either higher or lower in the RPM range. This is only recommended if u are absolutely certain u can accurately diagnos an over advanced condition anywhere in the entire RPM range, as such a condition can quite easilly cause engine damage &/or failure.
So, until they're posted in a day or 2, dont buy an aftermarket CDI. Basic soldering skills can be learned in minutes & even if u know nothing about electronics u'll have no problem at all building a CDI from this layout. Cheers
how much do you think the components would cost in total? And the aftermarket Jaguar CDI is only $25, it's the coil that JN Motors includes (A KDX coil or something like that) thats the expensive part (However you can buy the CDI directly from jag and go for a cheaper coil, but compatibility tends to be an issue, thats why JN includes the coil now). If we could find a way to build both into one like the stock CDI's that would be space saving and awesome, and save some money.
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Hi, IIRC, the last one I built for someone a few months back came to a total of au$17, using high quality components, board & all. That was buying over the counter at the local electronics outlet, & with all resistors being in an 8 pack (26 cents per pack). Buying components in the US u can expect to pay a good bit less. (when I built valve (tube) guitar amps I order most all compinents from the US, & even with shipping its cheaper than buying here & thats including heavy items like transformers).
The CR80 coil gives the hottest spark apparently. A quick search on ebay & the 1st & only one I looked at is US$10.95. Most coils off small MX bikes will work. Some have only 1 connection to the CDI, in which the output to the coil goes to this while the black lead from ur magneto to the CDI also goes to the core that runs thru the center of the coil. Connect using an electrical eye connector to one of the mounting bolt holes. The CR80 coil is this type. The other type has 2 connections to the CDI where both the output from the CDI & the black leads connect. I use a coil off like a 500cc rhat I scrounged & the CDI has no problem sparking it.
I am going to my friends to get the layout & shematic diagrams up here this arvo. Over the next few days I'll get a complete component list etc up here. I would recommend ordering components thru a reputable supplier like Mouser or Digikey as ur guarenteed to get quality components, which u at least want for the C106D1 SCR & the polypropylene charge caps. I'll also post a simple method of testing the SCR using a battery & small light bulb, for those who choose to buy this from ebay. cheers
The CR80 coil gives the hottest spark apparently. A quick search on ebay & the 1st & only one I looked at is US$10.95. Most coils off small MX bikes will work. Some have only 1 connection to the CDI, in which the output to the coil goes to this while the black lead from ur magneto to the CDI also goes to the core that runs thru the center of the coil. Connect using an electrical eye connector to one of the mounting bolt holes. The CR80 coil is this type. The other type has 2 connections to the CDI where both the output from the CDI & the black leads connect. I use a coil off like a 500cc rhat I scrounged & the CDI has no problem sparking it.
I am going to my friends to get the layout & shematic diagrams up here this arvo. Over the next few days I'll get a complete component list etc up here. I would recommend ordering components thru a reputable supplier like Mouser or Digikey as ur guarenteed to get quality components, which u at least want for the C106D1 SCR & the polypropylene charge caps. I'll also post a simple method of testing the SCR using a battery & small light bulb, for those who choose to buy this from ebay. cheers
