COP's Harness pics

[satariel666]

My previous post isn't meant to put the kabash on COP's. But rather it's meant to stake out a starting place in my mind. As far as I'm concerned I'm just cranking up my problem solving mode.

This is what an OEM ignition waveform looks like on an oscilloscope:

The scope tells me the following:

The OEM coil is charged for 8 milliseconds (0.008 seconds) with 12 volts. At the very end of the 8 millisecond period the plug is fired and the spark lasts for around 1 millisecond. The peak reverse voltage (PRV or PIV)) seen by the OEM TCI module is around -15 to -20 volts.

When I get my loaner cops I'll again do this test while using various resistors and determine what resistor best reproduces the same load on the OEM TCI module as we don't want to stress it out. I'll also adjust the resistor to limit the energy to the cop to its normal maximums. I have no idea (other than in my previous post) as to how this will come out.

One last thought: There are likely some efficiency losses when using a separate ignition coil and spark plug wire but not a lot. Manufacturers went to using cops because it's cheaper and easier for them. Then, given that the traditional coil/plug setup is about the same efficiency as the cop solution then the one difference glaring difference is the size of the coils and their close proximity to engine heat. The cops is a lot smaller and therefore will not be able to transfer as much energy as a large external coil; and, because of the heat, it will not be able to be driven as hard as an external coil.

That said, I'm hoping for a good surprise when I begin my testing with the cops. I hope that I'm underestimating their performance. I want them to work! We know that others are using them and have quite a few miles on them at this point. That is a great sign that either the calculations are pessimistic or that the OEM TCI module is more robust than expected.

Nice gear, I have similar at work but honestly I never felt a need to test my coils like that.

Id like to see the results but I still dont get the idea WHAT FOR?

 

[satariel666]

Are you guys saying, that even with stock ignitor boxes (TCI)
that we should a resistor in series with the denso cops ?????
<<Dave>>unk:

IMHO no.

Until You pick up good DENSO's it will work just fine.
As many of us doing from a long time.

 

[Bon-86]

Nice gear, I have similar at work but honestly I never felt a need to test my coils like that.

Id like to see the results but I still dont get the idea WHAT FOR?

You may have found a great match between your bike and cops that work for you and that's awesome.

However, even within the Denso cops line there are different electrical RLC characteristics. Denso makes their cops to each OEM's specifications so it's not a one size fits all product. Each manufacturer has their own engines, electronic ignition systems, firing patterns, rpm ranges, CDI and inductance ignition systems and even single/double pulse plug firing schemes. In addition there are at least three different ignition boxes in use.

I'm trying to look at the broader issue of how to look at any cops and ignition module and get the most bang-for-the-buck. I define the most bang-for-the-buck as when I'm pumping the maximum charge into the cops that will not overload or overheat it and when I'm not at risk of OD'ing the ignition module from over-current or excessive peak reverse voltage. COP's are cheap but the TCI modules aren't and carrying a spare isn't going to happen.

 

[satariel666]

You may have found a great match between your bike and cops that work for you and that's awesome.

However, even within the Denso cops line there are different electrical RLC characteristics. Denso makes their cops to each OEM's specifications so it's not a one size fits all product. Each manufacturer has their own engines, electronic ignition systems, firing patterns, rpm ranges, CDI and inductance ignition systems and even single/double pulse plug firing schemes. In addition there are at least three different ignition boxes in use.

I'm trying to look at the broader issue of how to look at any cops and ignition module and get the most bang-for-the-buck. I define the most bang-for-the-buck as when I'm pumping the maximum charge into the cops that will not overload or overheat it and when I'm not at risk of OD'ing the ignition module from over-current or excessive peak reverse voltage. COP's are cheap but the TCI modules aren't and carrying a spare isn't going to happen.

Mine densos are 1,8 Ohm.
I've heard about 1,3/1,5/1,6 Ohm COP's according to mambers here and thier messurements.

I think the problems with COP's and the v-max is that they cant be used with DYNA 3000. According to COP's/stock TCI users evrything is fine.
Looks like there's no any issue, besides the Mitsubishi COP's.

The only reason that I was serching for good resistor was the posibility of using COP's and DYNA, which was done with a good result.

Personaly I dont care about "eternal life COP's" as I can always buy new ones for 30$. At this moment mine COP's working good for a long time.

If You have that posibilities to dig this more, thats great.
Please share the results, Im alwyas open to new ideas.

Only thing that Im wonderig is: who will use Your work?

 

[88vmx12]

Mine densos are 1,8 Ohm.
I've heard about 1,3/1,5/1,6 Ohm COP's according to mambers here and thier messurements.

I think the problems with COP's and the v-max is that they cant be used with DYNA 3000. According to COP's/stock TCI users evrything is fine.
Looks like there's no any issue, besides the Mitsubishi COP's.

The only reason that I was serching for good resistor was the posibility of using COP's and DYNA, which was done with a good result.

Personaly I dont care about "eternal life COP's" as I can always buy new ones for 30$. At this moment mine COP's working good for a long time.

If You have that posibilities to dig this more, thats great.
Please share the results, Im alwyas open to new ideas.

Only thing that Im wonderig is: who will use Your work?

Satariel, I want to know for sure about the outcomes. I have been doing some research on the Denso COPs myself and found that there really are not that many diffent model #'s I want to find out more from the users here on the forum such as length , resistance, and the model # they are using. That way we can for sure find out what model #'s are the best the ultimate outcome ! Gannon

 

[88vmx12]

Also if I need to put a resistor inline on any of these. I would be willing to make some custom harnesses if need be to save someone from having to go out and buy a new set of COP's. Ultimatley having to spend more money !

Thanks for all the imput on this guys, we will make sure one way or another that we are all happy
Gannon

 

[satariel666]

Satariel, I want to know for sure about the outcomes. I have been doing some research on the Denso COPs myself and found that there really are not that many diffent model #'s I want to find out more from the users here on the forum such as length , resistance, and the model # they are using. That way we can for sure find out what model #'s are the best the ultimate outcome ! Gannon

They could be diffrent.
For example I have Kawasaki ZX10R,ZX12R and CBR600RR manuals.

ZX10R service says 1,2-1,6 Ohm for stick coils.
ZX12R service says 0,85-1,15 Ohm
CBR 600 RR says 1,5-1,8 Ohm.

 

[MikeTD3]

Bon-86, I appreciate the extra effort and info....when I do decide to go this route I want to do it once, and do it right.

 

[88vmx12]

Bon-86, I appreciate the extra effort and info....whne I do decide to go this route I want to do it once, and do it right.:clapping:

High Five! Mike

Gannon

 

[Bon-86]

Nice but You forgot about voltage drop...

Are You sure that COP controls the charge duration itself? Nah, TCI do.
So with COP it still takes 8ms, right?

I'm not sure what voltage drop you're referring to.

The TCI controls the time that the COP has to draw current. The inductance of the COP "resists" the change in current so the voltage presented to the COP takes some time for current to flow and reach its V/R limit. The inductance of the windings store energy in the electrical field created by the current flow. Once the current flow reached its V/R limit then no more energy will be stored but rather only heat is generated. The TCI drives the current for 8ms regardless.

By looking at the COP from an energy (Joules or watt-seconds) standpoint then it gets pretty easy to pick the correct resistor for best performance. If we establish that we want to consume 0.25 Joules with each spark then the formula is 14*14 *.008 / 0.25 = 6.27 ohms. This is total ohms. If the COP is a Mits 0.3 ohm then the limiting resistor is 6 ohms. If a Denso 1.5 ohm COP then its still 6.27 total ohms but the limiting resistor is now 6.27 - 1.5 = 4.75 ohms.
The combined resistance is the same for any COPS used when the energy is a constant.

The wattage of the limiting resistor is influenced by a number of things: type of engine (4 stroke, 2 stroke), number of cylinders, firing pattern, wasted spark and average rpm. It's not affected by the COP used as long as you design for a specific spark energy. In short, the V-Max ignition will burn about 1 watt per 1,000 rpm PER CYLINDER. If you average 3,500 rpm then the resistor will average about 3.5 watts per cylinder. Consideration must be given to the hot environment that the resistor is soaking in and if it doesn't have free air movement such as inside a sleeve. There isn't any penalty for over-sizing the resistor wattage but the above should help in selecting one.

I hope to look at using a single, higher wattage, resistor instead of 4 discrete resistors and place it where the coils are/were just above the battery. This way I will only need the clean wiring harnesses that are being made by 88VMX12.

 

[satariel666]

I'm not sure what voltage drop you're referring to.

The TCI controls the time that the COP has to draw current. The inductance of the COP "resists" the change in current so the voltage presented to the COP takes some time for current to flow and reach its V/R limit. The inductance of the windings store energy in the electrical field created by the current flow. Once the current flow reached its V/R limit then no more energy will be stored but rather only heat is generated. The TCI drives the current for 8ms regardless.

Voltage drop on added resistor.

So why v-max needs as much as 8ms of charge?
Its carburated I guess. Modern EFI bikes precisly injected needs
3-4ms those days, some even less.
Aftermarket EMS's provides ajustable charge which will end any of those problem.

By changing the parameters of the reciver You will not change parameters of the transmiter. By this way stll geting 8ms charge You are right, couple of Ohm resistor will take about half of that charge and transform this energy into heat.
But by changing charge in this PASSIVE way the hudge part of spark energy will go to the resistor.



But whats left to coil?
In the matter of fact its not a coil, its transformer. Yeah I know, transformer is
a element bulid from 2 coils, coils magneticly coupled.
And evry transformer have its ratio. The rule is simple. As much taken from the primary side and much less given on the secondary side - of course this is
strongly definite by specific formula.



Im afraid that with that kind resistor added there will be not much energy/spark left.

 

[Bon-86]

Voltage drop on added resistor.

So why v-max needs as much as 8ms of charge?
Its carburated I guess. Modern EFI bikes precisly injected needs
3-4ms those days, some even less.
Aftermarket EMS's provides ajustable charge which will end any of those problem.

By changing the parameters of the reciver You will not change parameters of the transmiter. By this way stll geting 8ms charge You are right, couple of Ohm resistor will take about half of that charge and transform this energy into heat.
But by changing charge in this PASSIVE way the hudge part of spark energy will go to the resistor.



But whats left to coil?
In the matter of fact its not a coil, its transformer. Yeah I know, transformer is
a element bulid from 2 coils, coils magneticly coupled.
And evry transformer have its ratio. The rule is simple. As much taken from the primary side and much less given on the secondary side - of course this is
strongly definite by specific formula.



Im afraid that with that kind resistor added there will be not much energy/spark left.

The large discrete coil of the OEM coil needs longer to charge. A COP is much smaller and needs less time/energy to charge. I understand its a transformer but I just use the traditional language and call it a coil. The limit resistor is just a loss but since we can't change the 8ms in the OEM TCI it's the only way we have. Remember, we only need enough spark to ignite our fuel charge and not have the spark extinguished by turbulence or too rich a mixture such as when the engine is cold and on choke or when the battery is low on charge or low on voltage such as when starting. The longer time of 8ms is good to have at those times. But at other times the excess current flow is just waste heat.

 

[satariel666]

So let me be Your spectator, thums up.

I very curious with the results.

Keep us informed!

 

[88vmx12]

I have a feeling that we will have a better feeling of what is needed by the end of the week! Who knows for sure, please be patient unless some who want these harnesses. I can make them without a resistor in them. Then you can add it later or not at all.
Without resistors will be $50

Thanks Gannon

 

[Bon-86]

Well, I've been busy. I've been experimenting with Denso cops and resistors between 1 ohm and 6 ohms. I've been using a Fluke temperature meter with bare wire thermocouples to watch the temperatures of the COPS and resistor. I changed my approach a bit and began to monitor the current that is flowing through the COPS rather than the voltage. I did this because it seemed that current was the greatest thread to the TCI box.

I first wanted to determine the worst case temperature environment that a COPS is normally subjected to. So, I began by monitoring the temperatures of my OEM Denso COPS on my car. This seemed to be a worst case scenario because the COPS is buried in a metal tube that is sunken down into the the head. I found that the worst case is a long highway drive rather than around town traffic. The COPS in the car reaches around 220 degrees F max.

I then installed a COPS on my Max with several values of cement power resistors. I installed a 1 ohm 10 watt and took temperature measurements while riding and standing. I also installed a 3 ohm 10 watt resistor and repeated the test. The 1 ohm is what a lot of folks are using right now and the 3 ohm resistor provides enough current to the COPS without as much stress on the TCI as even the OEM coils do.

The COPS and resistors reached a max temperature of around 155 F. The COPS gets hottest when when the bike is stopped. Engine heat without a cooling airstream is responsible. The resistor reaches maximum temperature at speed since it is somewhat removed from the engine heat and max current flows through it as the highest rpm's.

Cheap cement power resistors are good for about 350 F so no worry there. COPS are regularly subjected to around 220 F in car engines so no worry there.

Looking at the current that the TCI is handling I found:
OEM coils - 3.45 amps
Denso COPS with 1 ohm resistor - 3.87 amps
Denso COPS with 3 ohm resistor - 2.52 amps

The bottom line:
The oscilloscope traces show that the TCI does not have any problem establishing maximum current flow through the COPS with either resistor.

I was only using a single COP while riding around and could not tell any difference between the 1 ohm and 3 ohm setup.

As I'm riding an '86 with the OEM analog TCI box I'd personally opt for running with the 3 ohm setup to reduce the stress on my 24 year old TCI box.

The 10 watt resistor did just fine even with 20% of its body wrapped in electrical tape for the thermocouple temperature measurements. I'd likely spend a little more on premium 12 watt resistors that are good for nearly 600 F for maximum reliability.

I would not run any COPS without an added resistor.

 

[satariel666]

Good job, nothing new tho.

Stock TCI will work fine with COP's, there are 8A transistors inside.
No need for resistor, the fried TCI's were older types and they commonly know as "not reliable"
Newer type TCI is almost indestructable, never heard about one bad.

DYNA 3000 use weaker transistors, 5A and here is the problem You should examine.

 

[Bon-86]

The "new" here are facts instead of hunches and guesses mixed in with antidotal experiences.

Stock TCI with 1.5 ohm Denso's without resistor can draw 9+ amps. Not so good for 8 amp transistors. And a good design doesn't work components to their maximum limit. Rather the working design maximum is very close to 1/2 of a components maximum ratings.

Those of us with pre 1990 older Max's have to live with our "not reliable" TCI's and should seek to protect them or pay the price. Dyna 3000's aren't available any longer for our older bikes so our options are? . . .

 

[spursmech]

:ummm: Hey, what's the point of this Modification? There is no more HP made and the reliability seems to be bad. So why do it? Just asking, Spurs

 

[KJShover]

:ummm: Hey, what's the point of this Modification? There is no more HP made and the reliability seems to be bad. So why do it? Just asking, Spurs

Some say thier bike runs a little more crisp, and starts a little easier. Easy install and not all that expensive compared to replacing the factory coils.

I found with the 8mm wires+NGK caps with my Dyna3k, it starts better and has a more crisp throttle response.

 

[satariel666]

The "new" here are facts instead of hunches and guesses mixed in with antidotal experiences.

Stock TCI with 1.5 ohm Denso's without resistor can draw 9+ amps. Not so good for 8 amp transistors. And a good design doesn't work components to their maximum limit. Rather the working design maximum is very close to 1/2 of a components maximum ratings.

Those of us with pre 1990 older Max's have to live with our "not reliable" TCI's and should seek to protect them or pay the price. Dyna 3000's aren't available any longer for our older bikes so our options are? . . .

No offence Bon but I cant say those are facts, You definitly missing some things.
The highest messured current on COP without resistor was 6A at very high revs if I remember correctly.
More then that, those transistors are 8A constant load and 16A peak load.
More then needed, I say 3/4 load of total and they are very safe, thats exactyl what I saw in many devices in my life.
The best fact will ba many v-maxers running with COP's and thier TCI's are still fine.

Options?
Try to repair old type TCI, You will surely see that they fail cause is not related with current overload.
Been there, repair some.
As an replacments for fried transistors Im using 15A constant and 30A peak ones.

To bad that people use to give me fried TCI's with absolutly no any symphtoms descriptions. I must check evrything.

I dont have anymore someone with old type ignition to check the repaired unit.
Im curently bulding the testing jig for TCI's.

Again, I ilke Ypur work. Good luck.