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QUOTE (kawiking @ Nov 17 2008, 06:32 AM) index.php?act=findpost&pid=16350whats the pros and cons of a dyna cdi..

im thinkin about gettin one for the bike

Thats a good question. i have one on my bike already with a small black switch on it. have no clue what its all for. im interested to see what paople have to say about it.
 

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I think there will be a small debate from different people as to who thinks it's a good investment and who thinks it's not worth it. I run one, love it. I picked it up last year to replace my stock CDI and noticed a difference just from hooking it up and running the stock curve. I can't tell you exactly how much it improves over stock, in stock form, but I could definitely tell a seat of the pants difference, and also have the luxury of re-programming the curve to fit my application, and create a separate curve for when I want to spray nitrous. But you must have the CD and cable to re-program the ignition.

The little box you're talking about is the dipswitch. That is how you tell the ignition which curve you want to run. If your box is not re-programmed, it has 4 different curves in it, and you can choose which one you want by changing the settings on the dipswitch. It should be labeled with a sticker indicating which settings you need to have on the switch to get whichever curve you like. I have a diagram at home that shows the different curves and can upload it later on.
 

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QUOTE (bigboybanshee @ Nov 17 2008, 12:06 PM) index.php?act=findpost&pid=16419I think there will be a small debate from different people as to who thinks it's a good investment and who thinks it's not worth it. I run one, love it. I picked it up last year to replace my stock CDI and noticed a difference just from hooking it up and running the stock curve. I can't tell you exactly how much it improves over stock, in stock form, but I could definitely tell a seat of the pants difference, and also have the luxury of re-programming the curve to fit my application, and create a separate curve for when I want to spray nitrous. But you must have the CD and cable to re-program the ignition.

The little box you're talking about is the dipswitch. That is how you tell the ignition which curve you want to run. If your box is not re-programmed, it has 4 different curves in it, and you can choose which one you want by changing the settings on the dipswitch. It should be labeled with a sticker indicating which settings you need to have on the switch to get whichever curve you like. I have a diagram at home that shows the different curves and can upload it later on.


that would be awesome. this think was from a mx bike. so im not sure what i need to do to get the curve that i want. im sure that the curve that is on it is probably not the right one for drag racing if this was a mx bike.
 

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If i remeber correctly that when you put a dyna on vs's the stock one, the stock timing on the dyna is 4 deg's advance so that is probally what you felt when you put it on.

I am not 100% for sure but i do remeber reading that somewhere before.
 

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QUOTE (BBIII @ Nov 17 2008, 02:19 PM) index.php?act=findpost&pid=16422If i remeber correctly that when you put a dyna on vs's the stock one, the stock timing on the dyna is 4 deg's advance so that is probally what you felt when you put it on.

I am not 100% for sure but i do remeber reading that somewhere before.

You are correct.

I've got a few of my own thoughts.

For a smaller motor, unless you're going to use it to it's potential...I don't think it's worth it.

If you have the time/means to program it on a dyno...and "tweak" it at the track...good investment.
They have other options tied into them as well (NOS activation, ignition studder...I think...)
Like Big Boy said... The option to have a NOS curve, alky curve...or other curves (1/8 mile, gas, etc.) are a benefit for sure.


If you have a much bigger motor, or a BIG single, they are a must.

For example...

Neal's big Saber would probably break your foot, or parts...without this ignition. they program it with little or NO timing for the first 1000 or 2000 RPM just so they can start the beast.....
 

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QUOTE (dajogejr @ Nov 17 2008, 12:26 PM) index.php?act=findpost&pid=16423You are correct.

I've got a few of my own thoughts.

For a smaller motor, unless you're going to use it to it's potential...I don't think it's worth it.

If you have the time/means to program it on a dyno...and "tweak" it at the track...good investment.
They have other options tied into them as well (NOS activation, ignition studder...I think...)


If you have a much bigger motor, or a BIG single, they are a must.

For example...

Neal's big Saber would probably break your foot, or parts...without this ignition. they program it with little or NO timing for the first 1000 or 2000 RPM just so they can start the beast.....

so far my bike has ran good with it. im just curious if it was getting its full potential? also curious if i should put a stock one back on or just leave it on.
 

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QUOTE (dajogejr @ Nov 17 2008, 12:29 PM) index.php?act=findpost&pid=16425I don't think you're getting it's "full" potential until you dyno and track tune the curves.

As with anything electrical, I've learned to keep spares in the box.


i have the stock wiring still. was kinda unsure if i had enough motor to mess with the dyna.
 

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QUOTE (BBIII @ Nov 17 2008, 12:19 PM) index.php?act=findpost&pid=16422If i remeber correctly that when you put a dyna on vs's the stock one, the stock timing on the dyna is 4 deg's advance so that is probally what you felt when you put it on.

I am not 100% for sure but i do remeber reading that somewhere before.

You are right, there is a 4 degree advance over the stock CDI's curve. When I did my testing, I had my timing plate on +5 with the stock CDI, then put the plate to 0, hooked up the dyna, and that's when I noticed the difference. So even with less timing, it still ran better and turned a better ET than a stock CDI, for my application. (4mil cub, 68mm bore). Then I moved it to curve 3 and noticed more gain, then started upping the timing on the plate and throwing more fuel to it until I found my sweet spot.

I think it's a worthwhile investment if you're willing to take the time to play with it...but that's just my


I don't think you need to dyno tune it, simple track time and reading your plugs will tell you where the best gain is...another opinion of mine.

JTraptor, what are your current settings for timing, fuel, etc.?
 

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luckily the bike i picked up had one on it already. i was thinking about selling mine until this post. good thing i didnt. seems like a good keep if i ever go bigger.
 

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I would keep it if you already have it....

Since I plan on spraying this year, it might be an investment I make again ( I sold my last one)
The nice thing about a dyna is a dynamic advance, in other words...8 degrees advance over the stock curve does NOT mean 8 degrees higher at the upper RPMs.

You actually want less timing at higher RPMs for more over-rev... With a plate, it's a static increase across the board (although the stock CDI does retard the timing at higher RPMs already...)
 

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I have some pre-made curves for them, one for alky and another for gas that I program in for $50. I knock down the lower end for easier starting (especially on big motors), and knock down the overrev to combat detonation. I feel much safer sending somebody down the road than if they had either the stock cdi curve, or the stock dyna curves.
 

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QUOTE (REDLINE @ Nov 17 2008, 01:44 PM) index.php?act=findpost&pid=16438I have some pre-made curves for them, one for alky and another for gas that I program in for $50. I knock down the lower end for easier starting (especially on big motors), and knock down the overrev to combat detonation. I feel much safer sending somebody down the road than if they had either the stock cdi curve, or the stock dyna curves.

what would i have to do to have you do something like that to mine.
 
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