Roll Your Own CDI
- Thread starter rohmell
- Start date
today i got my homemade intake done so i mounted my 19mm carb to my bike, it runs great and i love the intake sounds, sorry that was little off topic.
maby i order another stock cdi so i can put my rev limiter to it. or then i have to build the simple cdi and put my limiter to it.
maby i order another stock cdi so i can put my rev limiter to it. or then i have to build the simple cdi and put my limiter to it.
rohmell
Active Member
I am thinking that using a zener diode for more precise cut-off point.
Pienso que el uso de un diodo Zener de corte más preciso momento.
kusanagy100
New Member
clear zener diode regulating magnet CArectificada and filtered with a potentiometer to adjust the level to taste.
it is clear that the zener would use it to have a standard of comparison?
would also be a possibility of including a control circuit long and that is exactly the same.
with respect to the above diagram that I put I wanted to know if this so well connected, and what would be the minimum value would have to give the resistance that accompany the pot for this driving is not in total or in court
--------
another question is:
the resistance of 47ohm and 560ohm what role specifically and graphically in the curve of progress since the capacitor varies the Q of the curve
doing very fine could be used to adjust these settings presets ideally one you see the engine off.
follow juicy good post: D
it is clear that the zener would use it to have a standard of comparison?
would also be a possibility of including a control circuit long and that is exactly the same.
with respect to the above diagram that I put I wanted to know if this so well connected, and what would be the minimum value would have to give the resistance that accompany the pot for this driving is not in total or in court
--------
another question is:
the resistance of 47ohm and 560ohm what role specifically and graphically in the curve of progress since the capacitor varies the Q of the curve
doing very fine could be used to adjust these settings presets ideally one you see the engine off.
follow juicy good post: D
Ratchetbirds
Member
how i can get i open my stock cdi so that i can get my hands on the components. aparently the components are surrounden by resin of somekind.
As far as I am concerned you cannot open it without destroying it. Look around the middle of this thread to see the pics I took of one I opened. The stock CDI is pretty much garbage in my opinion. I recommend building Rohmells' simple cdi which is basically the same as the factory unit, just much better quality components. The factory CDI's are constantly going bad and are a waste of money. The other weak point is the ignition coil in the CDI box. It is very small and nowhere near what should be used on our little china engines. Just my 2 pennies worth.
rohmell
Active Member
how i can get i open my stock cdi so that i can get my hands on the components. aparently the components are surrounden by resin of somekind.
It depends if the epoxy is based on an aromatic or aliphatic formula.
Overnight soaking in methylene chloride might plactisize and soften the epoxy so that it can be removed.
If methylene chloride doesn't work, then try some polar or chlorinated solvents - NMP (N-methyl pyrrolidinone), DEET (N,N-diethyl-meta-toluamide), chloro- or
dichlorobenzene, methyl isobutyl ketone, isophorone.
rohmell
Active Member
The zener would be your standard, comparing it to the magneto's rectified incoming voltage.
Your diagram is well connected, use 100 ohm pot, then no need for series resistors on high and low sides.
rohmell
Active Member
hmm maby its just better to build my own cdi and with it suzuki pv coil.
now im going to sleep.
Yes! This way you can be proud to use a CDI that you built yourself!
kusanagy100
New Member
no need some series resistor in each sides of pontentiometer?
and witch efect produces the 47 ohm and 560 ohm resistors in the retard curve?
and witch efect produces the 47 ohm and 560 ohm resistors in the retard curve?
kusanagy100
New Member
no need some series resistor in each sides of pontentiometer?
and witch efect produces the 47 ohm and 560 ohm resistors in the retard curve?
wath model of scr is used? tic 106d? bd 140?
and witch efect produces the 47 ohm and 560 ohm resistors in the retard curve?
wath model of scr is used? tic 106d? bd 140?
Ratchetbirds
Member
Yes, the feeling of putting it on and having it work very well is indescribable.
So a new thought, Rohmell. Ever hand wind your own magneto? I am heavily contemplating it right now. Have tracked down wire, have access to lathes, but I can do it without one. Was wondering your thoughts on wire size and windings. My Grubee manual said it had 4000 winds of fine wire on top and 390 turns of heavier on the bottom. Of course the fine wire is ignition, thick wire for the 6vdc output. The new windings I wish to apply are for ignition only. The original fine wire appears to be 34 gauge(.0063). I can get that size in a 2000 foot roll for about $15. And this IS magnet wire, insulated and all that.
GearNut
Active Member
decoherence
New Member
there is a motor rewinding place down the road from me..
i also have a spare mag coil that is fried.
i was thinking about having them rewind it w/o the an "accessory" winding.
as long as it isn't too expensive.
rohmell
Active Member
No need series resistors. The gate can be at either gnd or else SCR's cathode potential.
47 and 560 ohm and capacitor are a starting point for experimentation. curves will be different due to SCR DV/DT , triggering points and ignition coil winding impedance/reactance/inductance.
rohmell
Active Member
It would be interesting to wind your own magneto, and possibly maybe even your own ignition coil.
Someone could offer those parts as an upgrade to the stock magneto and CDI.
I don't think I would have the patience to sit and wind 4000 turns of hair-thin magnet wire onto a form. I think in five minutes of doing so, coils and forms, etc would be flying up in the air.
Someone could offer those parts as an upgrade to the stock magneto and CDI.
I don't think I would have the patience to sit and wind 4000 turns of hair-thin magnet wire onto a form. I think in five minutes of doing so, coils and forms, etc would be flying up in the air.
impression
New Member
haha yeah. I thought about making my own Ignition coil that would be good for 20,000v ( enough to create a good spark with the worst of spark plugs and weakest of stator as well as under 200 PSI compression)
my issue is that now i'm running the coil on the right ( orange top) and it generates more than 20k ( used a multimeter )
It's also oil filled as to keep the windings inside it cool and is completely sealed. Honestly i couldn't justify buying the parts and making my own when i got the above 2 coils at a buy 1 get 1 free bargain
what i want to do next is wind my own magneto (stator)
i'm still working on how many turns to give me 4.8v on the white wire @ 2000 rpm. THis is so lights ( led's ) will still run @ idle, yet won't create too much voltage as to blow everything when you rev the engine flat out.
Attachments
Ratchetbirds
Member
Hiya Gearnut,
Yes I read Norms work on rewinding and it has important info I will need to rewind my magneto, but everyone else's work is for trying to get better lighting from the white wire coil without dropping out the ignition. I could care less about the 6 volt circuit, I just want improved ignition...bigger, hotter spark. Ya know, more power <G>. So I guess I will be doing some research on a single coil magneto. Norm is an impressive individual with skills that seem to know no bounds. We are all lucky he shares with us. Him and many many others.
impression
New Member
That's easy.
Since you don't want to make the "white wire" do 3500 turns of 30 gauge wire instead of 3100 turns of 36 gauge...
the higher gauge wire will let you do more 'turns' and keep the same level of resistance, yet his way you will generate more voltage = stronger spark
I can do the math for you, but i'm just about to face-plant my keyboard. G'night all