HD LIGHTENING vs STOCK CDI DYNO!!!



FurryOnTheInside

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#2
Funny things like what?
Many people are retarding the timing of the stock CDI ignition by using an offset magnet key. Have you taken this into account, or only tested the Lightning versus the stock CDI with the stock magnet position?
 
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Street Ryderz

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#3
What he doesn't say is that the engine was set to make it's power cleanly with the stock cdi and then wasn't retunned for the different timming curve of the Lightning cdi and if you look at the torque readings the Lightning made way more power through out the range and if it was jetted it would have made more power than what was shown.
 

Stoneman

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#4
I can only imagine the lightening to suite a particular kind of build so this dosent surprise me

Adjustable is where it’s at ;)
 

Stoneman

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#5
What he doesn't say is that the engine was set to make it's power cleanly with the stock cdi and then wasn't retunned for the different timming curve of the Lightning cdi and if you look at the torque readings the Lightning made way more power through out the range and if it was jetted it would have made more power than what was shown.
Why would it need to be re jetted?
 


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#7
Robert Bianchi, do you honor freedom of speech? Some people were telling me if you don’t like something that gets posted on the Zeda Motorsports FB page, you delete it.

Is this true?
 

Stoneman

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#8
Becuase you can hear that it was rich in the top vs the stock cdi and the curve (though not much) retards the timming enough to not get a complete burn and therefore losses some power!
Being a dyno they should be reading air fuel ratios that’s for sure
 

Kpi890

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#9
So I’m a little confused here... does the lightning CDI retard the timing or what exactly does it do? I’m looking into experimenting retarding my timing but I cannot seem to find a good instructional video on how to do so and I don’t trust myself to do it correctly based on some pictures I have seen. Is here a way to retard the timing without moving the magnet key and all that?
 

FurryOnTheInside

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#10
So I’m a little confused here... does the lightning CDI retard the timing or what exactly does it do? I’m looking into experimenting retarding my timing but I cannot seem to find a good instructional video on how to do so and I don’t trust myself to do it correctly based on some pictures I have seen. Is here a way to retard the timing without moving the magnet key and all that?
There are two different meanings of retard. Both are relative to something.

If you "retard" the magnet position in relation to the crank you are bluntly altering the spark timing, and retarding the timing at all RPM relative to the stock timing. This is one meaning of retard.

The other (and perhaps the proper) meaning of retard (and advance) is relative to its timing at a lower RPM.
Two stroke CDIs should have a "curve". It seems that at some point, as you accelerate, as the RPM increases, the advancing of the spark timing needs to stop and then it should be retarding as the RPM continues to increase.

The stock CDI doesn't have a proper curve, it keeps on advancing. It may advance a little bit less as RPM increases but apparently not enough. The magnet key trick is just a (free!) way to make the best of the stock CDI that you already have.
Aftermarket CDIs do have a curve, but different CDIs have different timing curves.
The Jaguar designed CDIs have a choice of several (four?) different curves so you can experiment and see which one suits your needs without any further purchases. I'm fairly sure that none of the timing curves on the Jaguar designed CDI is the same as the curve of the Lightning, Lightning Bolt, etc. So you can only try every possibility by buying every product on the market.
 

Kpi890

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#11
There are two different meanings of retard. Both are relative to something.

If you "retard" the magnet position in relation to the crank you are bluntly altering the spark timing, and retarding the timing at all RPM relative to the stock timing. This is one meaning of retard.

The other (and perhaps the proper) meaning of retard (and advance) is relative to its timing at a lower RPM.
Two stroke CDIs should have a "curve". It seems that at some point, as you accelerate, as the RPM increases, the advancing of the spark timing needs to stop and then it should be retarding as the RPM continues to increase.

The stock CDI doesn't have a proper curve, it keeps on advancing. It may advance a little bit less as RPM increases but apparently not enough. The magnet key trick is just a (free!) way to make the best of the stock CDI that you already have.
Aftermarket CDIs do have a curve, but different CDIs have different timing curves.
The Jaguar designed CDIs have a choice of several (four?) different curves so you can experiment and see which one suits your needs without any further purchases. I'm fairly sure that none of the timing curves on the Jaguar designed CDI is the same as the curve of the Lightning, Lightning Bolt, etc. So you can only try every possibility by buying every product on the market.
If you were to purchase an aftermarket CDI which one would you go with and why? And is it worth it to do so?
 

FurryOnTheInside

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#12
If you were to purchase an aftermarket CDI which one would you go with and why? And is it worth it to do so?
The plan is I'll be getting a Jaguar designed adjustable CDI because the timing retards more at higher rpm than the other CDIs that are available and I believe that suits my needs.
If you are a commuter or long distance adventurer, if you're looking for reliability and smooth running then I think that is the best way to go. It also gives you a choice of four settings to try, so that you can have it's maximum curve for best bearing protection or its minimum curve for more power (or perhaps you can use the adjustment to adapt to later changes you might make to the engine).
A racer might prefer a CDI that retards less at the higher rpm. My understanding is that will give more power at the cost of longevity.

You don't see the peak combustion pressure happening but you can make assumptions about that or feel the effects..
When the con rod is at 90° to the crank position the piston can move away from the pressure of the combustion so that the bearings aren't stressed and the con rod can put a lot of torque on the crank, but it has little distance to move before the exhaust port opens and allows all that pressure to escape.
When the con rod and the crank position are in line, that's top dead centre, and the piston can't move away from the pressure at all.
So if the spark timing is too early the peak combustion pressure will spike, beating the crap out of the bearings and putting heat into the cylinder wall, piston, head; but too late and it has a shorter power stroke or whatever the technical term is.
Somewhere in between is the ideal.

The stock CDI with the offset magnet key is working well for me, it's certainly smooth at the low to mid range rpm, but I think it could be smoother at the top end.
The stock CDI with an offset key is unbeatable value for money because it's free and it only takes a few minutes to make a notch in the key.
I am sure that with the Jaguar designed CDI the bearings would last longer especially if I run the engine up to its top rpm. I never built the bike to go fast but it seems to be too fun to resist.
I don't need the engine to last forever but I need to get home from ~80 miles away with the trailer and all my camping and fishing and snorkeling gear so reliability is more important to me than speed.
 
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#13
Jag's workz on all the different set-ups you can throw @ it, cost up front is worth it in years added to engine life. Any engine, even stock.
 



Kpi890

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#16
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Does anyone have a video or link on how the Jaguar CDI works and how to adjust it for different setups? I am just about broken in on my newest build, about to re-jet and go from there. I am looking to buy 1 nice upgraded part for it right now and I was looking at either an upgraded CDI or an expansion chamber like the MZ 65 pipe or something. My setup is fairly stock at the moment I just have a higher compression head on it and I’m looking for a bolt on upgrade that I will notice a difference with.
 

gary55

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#17
View attachment 81847 View attachment 81848 View attachment 81849 Does anyone have a video or link on how the Jaguar CDI works and how to adjust it for different setups? I am just about broken in on my newest build, about to re-jet and go from there. I am looking to buy 1 nice upgraded part for it right now and I was looking at either an upgraded CDI or an expansion chamber like the MZ 65 pipe or something. My setup is fairly stock at the moment I just have a higher compression head on it and I’m looking for a bolt on upgrade that I will notice a difference with.
I would PM Stoneman about ithe CDI. The MZ 65 expansion chamber will most likely not fit your bike the way you have it set up. In the pic. you can see the pipe extends a good amount beyond the down tube and will hit your front tire. The Zeda 88 or thrust expansion chambers may be more suitable for your build. At any rate the most noticeable bolt on improvement is a expansion chamber.View media item 61220
 
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FurryOnTheInside

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#18
View attachment 81847 View attachment 81848 View attachment 81849 Does anyone have a video or link on how the Jaguar CDI works and how to adjust it for different setups? I am just about broken in on my newest build, about to re-jet and go from there. I am looking to buy 1 nice upgraded part for it right now and I was looking at either an upgraded CDI or an expansion chamber like the MZ 65 pipe or something. My setup is fairly stock at the moment I just have a higher compression head on it and I’m looking for a bolt on upgrade that I will notice a difference with.
The first things I'd add to that bike is a support for the muffler to take the weight off the exhaust studs, and a nice big free flowing air filter. Both of which are very cheap bolt on mods.
I would expect you'll have a higher top speed with an upgraded air filter.
 


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#20
Isn't more rpm with less horsepower what you get when advancing the cdi to the engine to maximize efficiency?
I believe Dan's cdi is a great efficiency upgrade to any 2 stroke build
 


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