Birdoprey's COP (Coils Over Plugs) Mod

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Man I enjoy this board more and more on a daily basis, people here can actually do math and stuff. Are you guys sure you're part of the internet?

Anyway I didn't find what I wanted online so a precise answer is still not at hand. However bearing in mind that both resistors in the circuit have to be considered before applying ohms law. The rise in current should be pretty negligible (wth is the resistance on the plug primary? cuz I'm not yanking one to find out).

Odds are, the stock unit should hold up unless it's woefully under engineered. Even if it is, a beefier aftermarket piece should solve any problems if they arise.

If anyone has the numbers handy on the plugs and the factory cdi, plug em into the standard formula (resistors in series = simple sum) and we'll know if the current exceeds the available output.


In the meantime, I'm going for breakfast, gotta maintain my figure you know.
 
You are correct it is the primary that we are discussing. Understanding that if I lower the resistance the current flow will increase, but in a 12V system and a 1 ohm difference we are not talking a lot of current here. I am wondering if this is assumption on someones part or did anyone out there have a CDI box burn up on them from running COPs?
originally i was going to use the denso cop's on a microsquirt system im building over the winter but thought i might try them on my other max and see how they work with the big bore motor.i dont have a spare cdi though and if the primary resistance is way off the mark im inclined to let some other guys run them for awhile first.the way i was going to fire the cop's through the micro squirt was to use a bosch 4 channel ignitor off a golf or other newer vw mainly because the microsquirt processor only has two channels and cant drive four coils even if the are low ohm logic style ones.im thinking this same ignitor may work if the coils pull too much from the stock cdi circuitry.i also thought of volt pull up circuitry or a 16 v system too but thats a stretch right now.to answer your question i dont think anyone has smoked a cdi as yet but they are just trying to be cautious as this mods is still in its infancy.-hasnt been tested much on this application.
 
Hey Guys I might have the answer. I was talking to one of the electricians here at the plant and he gave me a very simple answer. I told him what was going on and our concerns. The first question out of his mouth was.....
What is the fuse rated at for the ignition. I told him 10 amps. He looked me square in the eye and said you have answered your own question. I was like duh.:bang head:
He went on to explain that if the fuse is rated at 10 then the system is obviously designed to handle at least up to that and probably more like 12-15 amps.
Just thought I would pass that along
Cheers :punk:
 
FYI:
-running for a couple months now. I decided to try this summer after the "new" coils I got off eBay had small cracks kinda like the ones i already had. I am (and have been) experiencing an intermittent skipping/missing cylinder(s).
new Vmax coils and wires made it better, but not go away. this mod and the addition of a Dyna ignition made little change as well.

- First long (2 hours 110 miles one way) trip this weekend. did get a little better mileage- 38mpg. could have been the Dyna ignition and/or cold weather as much as the coils.
- blew Ignition fuse one time so far. I will put in a 10Amp circuit breaker vs fuse (since they blow slower and reset) today and see where it goes.
- these are R1 coils and I am running a Dyna ignition
-also intend to get non resistor plugs.
-I combined the Vmax and R1 harness then covered with braided metal mesh for RFI/heat/chaffing protection as well as looks.
- some have mentioned vibration. My answer to that was to use the stock plug boot OVER the boot that comes with the R1 coils and then slide the rubber shock/dust cover that comes on the R1 coils down the coil body until it contacts the VMax Camshaft covers. coils fit well.
-Stock Coils removed front and rear.
 

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FYI:
-running for a couple months now. I decided to try this summer after the "new" coils I got off eBay had small cracks kinda like the ones i already had. I am (and have been) experiencing an intermittent skipping/missing cylinder(s).
new Vmax coils and wires made it better, but not go away. this mod and the addition of a Dyna ignition made little change as well.

- First long (2 hours 110 miles one way) trip this weekend. did get a little better mileage- 38mpg. could have been the Dyna ignition and/or cold weather as much as the coils.
- blew Ignition fuse one time so far. I will put in a 10Amp circuit breaker vs fuse (since they blow slower and reset) today and see where it goes.
- these are R1 coils and I am running a Dyna ignition
-also intend to get non resistor plugs.
-I combined the Vmax and R1 harness then covered with braided metal mesh for RFI/heat/chaffing protection as well as looks.
- some have mentioned vibration. My answer to that was to use the stock plug boot OVER the boot that comes with the R1 coils and then slide the rubber shock/dust cover that comes on the R1 coils down the coil body until it contacts the VMax Camshaft covers. coils fit well.
-Stock Coils removed front and rear.

Just wondering if you are thinking non resistor plugs will help with the amp draw for the ignition circuit???
Not trying to be combative at all, just pointing out it is the primary side of the coil we have been talking about that causes the excessive draw on the ignition. Flame suit on:punk:

I do like the idea of sliding the OEM dust boot on the R1 COP. I am going to do that as soon as I get home.
Cheers
 
Just wondering if you are thinking non resistor plugs will help with the amp draw for the ignition circuit???
Not trying to be combative at all, just pointing out it is the primary side of the coil we have been talking about that causes the excessive draw on the ignition. Flame suit on:punk:

no worry here- I am just trying to get rid of the !@#$!#@$T!Y%U^%$!#ing stuttering when it runs. sometimes it runs fine, other times it misses. I have gone through electrical (I thought/think) possibilities, fixed some carb issues that the SOB who charged me $300 to rebuild dorked up (see pic). It is either a bad connection somplace or the/a plug is miss firing. so I figured I would get new plugs and try that.

Do you think going NR plug would make the coil draw more current ? I would think it would take less to fire an NR plug :confused2::confused2:
 

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Just wondering if you are thinking non resistor plugs will help with the amp draw for the ignition circuit???
Not trying to be combative at all, just pointing out it is the primary side of the coil we have been talking about that causes the excessive draw on the ignition. Flame suit on:punk:

no worry here- I am just trying to get rid of the !@#$!#@$T!Y%U^%$!#ing stuttering when it runs. sometimes it runs fine, other times it misses. I have gone through electrical (I thought/think) possibilities, fixed some carb issues that the SOB who charged me $300 to rebuild dorked up (see pic). It is either a bad connection somplace or the/a plug is miss firing. so I figured I would get new plugs and try that.

Do you think going NR plug would make the coil draw more current ? I would think it would take less to fire an NR plug :confused2::confused2:

David, try running the bike in a dark garage and see if you can see a spark jumping somewhere.

How new are your wires/boots? Have you tried putting your stock ignitor back on?
 
Just wondering if you are thinking non resistor plugs will help with the amp draw for the ignition circuit???
Not trying to be combative at all, just pointing out it is the primary side of the coil we have been talking about that causes the excessive draw on the ignition. Flame suit on:punk:

no worry here- I am just trying to get rid of the !@#$!#@$T!Y%U^%$!#ing stuttering when it runs. sometimes it runs fine, other times it misses. I have gone through electrical (I thought/think) possibilities, fixed some carb issues that the SOB who charged me $300 to rebuild dorked up (see pic). It is either a bad connection somplace or the/a plug is miss firing. so I figured I would get new plugs and try that.

Do you think going NR plug would make the coil draw more current ? I would think it would take less to fire an NR plug :confused2::confused2:

The amp draw is only going to be on the primary side of the coil. It is independant of the secondary side of the coil. The primary side amp draw is based on the input voltage, 12v, and the resistance of the primary coil; COP ~1.5, stock ~ 3. Since the coil is basically a transformer when the ignition interupts the voltage from the primary side it discharges through the secondary side greatly increasing the voltage. Depending on the coil windings this could be, and I am guessing, probably around 30,000-40,000 volts. By ohms law if the voltage goes up then the amperage must go down. So basically we are seeing very very small amperage on the secondary side. So to answer your question, finally, a NR plug will not cause the coil to draw more current. Basically all a resistor type plug does is help supress the Radio Interference from the high voltage discharge. Hope this answers your questions.
Electrical inganeers, please correct me if I am wrong.

Now on to your intermentint miss with the dyna. I had a Dyna until my R/R f*cked up and was putting out 19.5 volts and pretty much fried a lot of shit. Anyways I had a intermintent miss as well. When I went back to my stock ignition it went away. Well this is the only thing I could figure out and once again please correct me if my thinking isnt in the right direction. If you look at the curve for the Dyna
http://www.dynaonline.com/skins/downloads/instruct/D3K7-7.pdf
it has a dotted curve for partial throttle that is waaaay more advanced then the factory. For example at 4k rpm stock is 36 degrees. Dyna is 45 degrees. 5k stock is 37 dyna is 47. So basically it is 10 degrees more advanced at partial throttle. I would notice this when I got happy with the throtte. With the dyna the stutter would go away instantly and run like a raped ape. As compared to my stock ignition it runs smooth the whole time but doesnt have the kick to it when I get on it hard. Remember when you view the link above you have to add 10 degrees to their curves to compensate for our vacuum advancer. The way I know this is I called Dyna, they are here in So Cal and asked one of their engineers why their curves are less than our stocker curves. He said I was silly. I emailed him the link to the tech manual on vmaxoutlaw and told him the page number and to compare. He called me back the same day and told me I was the only one to notice that in all the years they had been selling them. He did some research and got back to me. He told me that the paper curves dont include the 10 degrees added by our vacuum advancers but the ignitor does take it into account. Maybe with the extreme advance we are getting some preignition and it might feel like a miss??????:ummm::confused2::ummm:
Cheers
 
I very much apologize to all for hijacking a great thread with my missing engine issues. I will immediately start a thread so as to redirect the great help I am getting from folks

See the soon to be published ""Daves skipping/ popping miss/partial fire problems , the Dark years"
http://www.vmaxforum.net/showthread.php?p=55534#post55534

Maleko89 and RagingMain- thanks SOOO much for the suggestions, will put all this and my answer in the new thread.. . .

Sorry guys
 
Dude dont worry about the thread hi-jack, we have an award for that. :punk::punk::eusa_dance::eusa_dance::biglaugh::biglaugh:
 
Hey Guys,
Found this website called 'Esper Racing Japan' a long time ago. I was looking through it just yesterday and take a look at what I found:
http://esper.jp/customing.php?cnt=110&page=12
Looks like those guys in Japan are doing the COP on their bikes also. If you translate it to English using Babelfish or something, it talks about the COP's using extra current for a more intense spark ( or something to that effect. The Jap to Eng translation is kinda rough).
Also, the Esper guys are doing crazy stuff with turbos over in Japan. Take a look at the gallery and the parts they sell. I just don't know how to get in touch with them. I don't see an email. If anyone here can help me with that one, let me know. I want to email them and talk about purchasing some parts.

Thanks,
Vinnie
 
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If you click this link, you should go right to the translater page:
http://babelfish.yahoo.com/translat...p/other.php?ON=30&lp=ja_en&btnTrUrl=Translate
The thing is, the translation is kind of poor to say the least. But what I think they are saying is that they are selling what they're calling a 'Direct Ignition System.' I also read on another translated page that they think that water may be getting in the cracks of the original coils. Seems their 'kit' is nothing more than the same COP's that we've been discussing here. And from the looks of the pics on their website, it looks like they are just directly plugging in the COP's into the original Vmax harness (again, the same that some of the guys are doing here). So, maybe we don't have anything to worry about???

Vinnie
 
Thanks Vinnie. The cracked coils look just like mine did when I did the COP mod, but the bike ran fine with them. Not like it ran with the COP's, but still it was decent.
A couple days ago I swapped the COP's back to the stock (cracked) coils, for a comparison check, and now it's breaking down at 5K rpm's! I think this is due to the disturbance the stockers got in removal, reinstall, etc.
I'm going back to the COP's this week to verify, but I doubt it will still break up at the 5K mark.
 

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