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TaKaI M-RAIKOU Super Coils!

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Hello everyone!

I figured the engineering thread would be the place to start discussing our products with everyone. I would also like to welcome any engineers, or technically inclined individuals to ask any questions so we can leave up a good technical resource for people that may want to know more.

The plan is to day by day adding images and technical information on the product and leave some time for any inquisitive people to ask any questions so that they can better understand the inner workings and performance advantages of the product. For anybody that is interested post any and all questions. So you are aware of my background I am an EE that worked for suppliers to GM, Ford, etc and have also been an EE instructor as well. Also, I am a firm believer that there is no such thing as a stupid question, especially if you are interested in the topic, so if you are interested please ask.

To start I would like to introduce our TaKaI M-RAIKOU SUPER COILS (raikou stands for Thunder god in japanese incase anyone is interested).

The M-RAIKOU is an improved version of our already high output lineup of WeaponX EFX and EFX2 super coils but are specifically made for bikes.

The first feature I will introduce is it's capability to convert many bikes to direct COP technology. (COP = coil on plug)

As some may have noticed, various bikes come with direct coil on plug technology while others do not. We should all note that 99% of all automobiles these days use COP technology in order to improve performance and efficiency of the engine. Many MX bikes have followed suit, but other manufacturers change year to year primarily due to cost reasons.

Why the conversion to COP is superior?

Let me know if anyone wants numbers but in basic form this is the explanation. The more interconnects / connection points between the coil and the spark plug the higher the potential losses. Every connection point has something called resistance and the potential to oxidise. Firstly, oxidation reduces the connections capability to conduct. Think about when a battery won't start a car. Its still connected fine but the oxidation prevents energy from flowing. In an ignition system this means poor spark performance and poor running characteristics. Also, any length of wire and in all connection points there is a set amount of resistance. Resistance is just as its name implies, it resists the flow of electricity causing electrical losses leading to a poor performing ignition system. It should also be noted that the higher the voltage the higher the losses so more connections on the high voltage side of the ignition coils are prone to greater losses then the low voltage side of the ignition coil.

Just how does our system work?

See the image below, for example. The newest RM450F uses a remote mount ignition coil with a connection to the ignition wire and another connection to the spark plug. TaKaI's M-RAIKOU super coil mounts directly to the spark plug removing a high voltage connection which improves electrical conductivity and performance of the ignition coil. The M-RAIKOU is a super high performance ignition coil which is designed to reduce high voltage losses.

If there are any questions so far let me know. :thumbsup: I will start getting into the differences of our coil vs similar Denso, etc, coils and what we do with 2 stroke applications that cannot be directly mounted.

EDIT - Added a picture of the conversion of a RM450F when prototyping

Coil vs Coil.jpg

ConversionRM250F.jpg

Edited by TaKaI
Adding picture

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If resistance is such a problem, then why do we use resistance wires and resistance spark plugs?

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raikou was also a pokemon.. sorry for the spam had to say it..

i grew up watching the show years ago

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my question is, i can see how its more reliable.. but if everything is still working properly on the oem part then is there a benefit of using yours..

or would one just need to hold out till failure does occur?

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If resistance is such a problem, then why do we use resistance wires and resistance spark plugs?

Great questions everyone.

First... let me throw out a couple of equations and explanations.

First for power loss due to resistance.

In the 2 pictures I am attaching you will see a typical circuit which I will break down for you. This is more geared towards our spark plugs but will give you an understanding of the losses involved.

25000 volts is a typical ignition coil output, an in series a spark plug wire and spark plug and then the spark gap which lowers to about 5000ohms when the spark is started.

I am using a simple equation, ohms law, to determine the current and voltage at the spark gap with a high resistance and with low resistance. All I did was total the resistance and find the voltage that was dropped due to every resistance in the circuit buy using the equation

I(current) = V(voltage)/R(resistance) finds current in the circuit

Current stays the same everywhere in that circuit so I then used

V(Voltage lost) = I(current in the circuit) x R(resistance total)

In the first diagram with a wire and 5000ohm spark plug (standard these days) the loss is 11313 volts and current is 2.281 amps meaning 13687 volts is available at the spark gap during the spark event.

The second diagram shows what happens when we remove a large resistance in the circuit. Our current doubles to 4.163 amps and the amount of lost voltage is 23.31 volts when all other scenarios, except the spark plug resistance, are created equally.

With the lowered resistance we now have 24976.69 volts available at the spark gap.

Now for the second part of your question, why really ARE we using resistors!?

Back in the 1950's it was introduced to remove radio HUMMMMM... in a running engine and we are still using the same old archaic technology.

Also, and this is a bit of a long explanation but bear with me, there is a phenomenon known as flyback voltages in regards to ignition coils. It is such a high powered device the output energy reflects back at the input to some degree. The resistors purpose is to prevent these flyback voltages from being too high (which created the radio humming) but as a result lowers power output at the spark gap causing poor running. The flyback voltage can cause what is called EMI or RFI interferences that cause odd behavior in electronics. The reason this happens is because of magnetics.... let me explain.

Ever hear of anyone trying to generate power from a power line hanging out at the street? Its true, and can be done because anywhere electricity flows a magnetic field is generated. If I move a completely separate wire up and down in relation to the magnetic field I can generate power in that same wire. (this is how a stator works and why the crank rotates a magnet around a bunch of wires) Now think about what would happen if I had a high voltage at the input of an ECU, it would generate a magnetic field, next to other inputs. It is possible to generate power and signals in other wires which can effectively "confuse" the ECU causing it not to run.

The trick is to remove resistances that don't cause this issue and improve performance.... but in our case..... we are also able to remove large resistances everywhere such as in the spark plugs because we have an ignition booster box (AtoMX) that cleans out these flyback signals while boosting ignition coil input energy. These days most late model OEM ECU's also have this ability (to remove flyback voltages) built in, it just depends on the quality of the unit. Why they are still using these spark plugs if they have electronics that deal with flyback voltages!? Federal guidelines (FCC regulations) for noise emisson at certain frequencies. I don't know about everyone else, but they can deal with the radio noise and I will reap the couple hp and fuel mileage I gain thanks.

For points type ignitions it's a little different, the resistor is used for FCC regulations and is used to reduce the current at the point so it won't wear as fast. You can use the AtoMX to help prevent this issue but again, it all comes down to if you want the power or if you want to appease the governments request to not "pollute" frequencies they have determined need to stay clean in free air.

raikou was also a pokemon.. sorry for the spam had to say it..

i grew up watching the show years ago

NP... Cool! I've always been a fan of Japanese culture.. it's different and out there. I appreciate outside of the box thinking.

my question is, i can see how its more reliable.. but if everything is still working properly on the oem part then is there a benefit of using yours..

or would one just need to hold out till failure does occur?

There are lots of advantages, including reliability, easier starting. Alot of people don't know this but professional MX race teams change ignition coils after every race. It's very common because the OEM ignition coils can't handle the abuse. They need the competitive edge and notice a drop in performance after each moto. We have had our coils on for several races with no drop in performance. They are meant to handle some supreme punishment and keep going. On a little different note, we have a MotoGP racer using our coils for over 4 years, no failure yet, all other teams are still changing out coils every race due to mild missing. I will get into some more technical differences as we go as well so you can understand the intricacies of ignition systems for yourself and understand what the difference is and how we improved on existing designs.

What will you have available for 2strokes

I have attached another image. It's a little higher power unit that frame mounts since it is a little bigger to bump up power and compensate for any ignition wire loss. We also include our 8.8MM diameter PowerCORE wire that lowers resistance and has an internal power reservoir to help boost ignition power output. The wire also reduces flashover (which I would also like to explain in depth in this thread), controls interference energy and has automotive grade connection points to prevent oxidation which ensures long life and reliable running. I will get into the nitty gritty of them in here as well. :thumbsup:

Resistance1.jpg

Resistance2.jpg

2strokeSuperCoil.jpg

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I would check your math again. The amperage you are using is on the low voltage side, not the plug side. Since supply voltage is 12V, output is 25,000V, current at the plug would be 12/25000 * 2.281 = 0.001A which would generate a voltage drop of 5.5V, hardly anything considering the supply is 25,000V. Because the current is so low, getting shocked by a plug wire will not kill you. It takes about 15mA across your heart to kill you about 15X more than your coil puts out. Grabbing onto a 25,000V high tension wire on the power line outside is another story, you will quickly be BBQ'ed since the current is effectively unlimited.

Also, the math is actually much more complicated than that since the coil generates more of an AC voltage than the simple DC that ohm's law uses. The resistance in the wire and plug lowers the voltage at the plug but actually increases the spark time.

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All YZF's have been COP since 2003. Most GM engines, and indeed, most modern automobiles and light trucks have generally gone to COP over the last 10 years or so. If heat were an issue, the underhood temps of the modern automobile would have killed off all of them by now.

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I tell you what, you design one of these for my 2011 kx and Ill give it a try and report back here!

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what country is it manufactured in?

the 2 stroke model looks like A COIL WITH A PLUG WIRE.

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I would check your math again. The amperage you are using is on the low voltage side, not the plug side. Since supply voltage is 12V, output is 25,000V, current at the plug would be 12/25000 * 2.281 = 0.001A which would generate a voltage drop of 5.5V, hardly anything considering the supply is 25,000V. Because the current is so low, getting shocked by a plug wire will not kill you. It takes about 15mA across your heart to kill you about 15X more than your coil puts out. Grabbing onto a 25,000V high tension wire on the power line outside is another story, you will quickly be BBQ'ed since the current is effectively unlimited.

Also, the math is actually much more complicated than that since the coil generates more of an AC voltage than the simple DC that ohm's law uses. The resistance in the wire and plug lowers the voltage at the plug but actually increases the spark time.

Even when the pulse width is small it is still 100% considered a DC voltage. Impedance is not a factor in the ignition system input regardless of frequency of the pulses. (if that is what you are eluding to) This is because the current never changes directions and is always positive based, but, you are correct in your observations with current output. Wattage in equals wattage out but I am trying to give an easy explanation without going into the complexity of the overall circuit. EDIT - Just thought about this, or perhaps you are eluding to voltage over time constant in charging of the coil? Even at that, it has nothing to do with "AC power".

The jist of the explanation is the higher the resistances the greater the voltage drops and capability of voltage at the spark gap which is responsible for reliably igniting the air fuel mixture every power stroke.

All YZF's have been COP since 2003. Most GM engines, and indeed, most modern automobiles and light trucks have generally gone to COP over the last 10 years or so. If heat were an issue, the underhood temps of the modern automobile would have killed off all of them by now.

If I am not mistaken they just changed back to separate coil and plug wire for this model year. Also, not to mince words but, I never said heat was an issue for a properly engineered coil. What I said was that race or teams change coils routinely because of failure, primarily due to the design of the coils used on bikes. We are all free to find the truth and ask any professional but I wouldn't have put it out there if it wasn't true.

I tell you what, you design one of these for my 2011 kx and Ill give it a try and report back here!

Thanks for the offer, but like I said, we already have some renowned teams that have tested the product. I can't talk names just yet.

what country is it manufactured in?

the 2 stroke model looks like A COIL WITH A PLUG WIRE.

Built and designed in Canada.

Yes it is a coil with a wire. There is no room to properly support a COP conversion on the 2 strokes since the plug is on the very top of the head, where 4 strokes project in due to the cams, but there are allot of other benefits that have been engineered into the coil and wire. I will get into explaining the whys in this forum.

Is there a COP suitable for a Honda XR400 ? The XR400 can run very hot. I like the idea.

TomR, we have a coil here but we do not have a bike. If you want to work with me I can let you know if you have the clearance and room necessary for the COP conversion to work. Send me an email to support@takai-racing.com and we can talk.

:thumbsup:

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I have attached another image. It's a little higher power unit that frame mounts since it is a little bigger to bump up power and compensate for any ignition wire loss. We also include our 8.8MM diameter PowerCORE wire that lowers resistance and has an internal power reservoir to help boost ignition power output. The wire also reduces flashover (which I would also like to explain in depth in this thread), controls interference energy and has automotive grade connection points to prevent oxidation which ensures long life and reliable running. I will get into the nitty gritty of them in here as well. :thumbsup:

So is make/model specific and is it available.

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So is make/model specific and is it available.

Yes, they are make and model specific and they will be available in 1 - 2 weeks. Do you have an application you would like me to verify?

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the 2 stroke model looks like A COIL WITH A PLUG WIRE.

Since the plug in most two strokes is not down inside a deep well, there is nothing to support the weight of a COP coil other than the plug insulator, which would be a shaky setup (sorry about the pun). There could be clearance issues.

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Since the plug in most two strokes is not down inside a deep well, there is nothing to support the weight of a COP coil other than the plug insulator, which would be a shaky setup (sorry about the pun). There could be clearance issues.

lol... Yes, that would be a shaky setup! and why I wouldn't recommend it!

Absolutely, we work on a bike by bike basis, and you are correct, some setups are worse/better than others. We have actually seen the spark arch through the ignition wire on some setups directly to the frame. I agree 100% that it isn't a common problem but there are some late model bikes (cough cough CRF) that we have seen this issue on more than once. At the very least we design our ignition wire and coils to direct the energy where it needs to be and make all setups as reliable as possible.

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If I am not mistaken they just changed back to separate coil and plug wire for this model year. Also, not to mince words but, I never said heat was an issue for a properly engineered coil.

The 2010 model YZ450F did revert to the separate coil setup in order to increase the size and output of the coil. This and other changes were made due to the fact that the fuel pump on the EFI system runs only off of generator current while starting, which puts the overall efficient use of available current at a premium during start up. Once running, the system has a considerable surplus energy potential.

The YZ250F continues to use COP.

You didn't mention heat, someone else did. I made that point to illustrate that heat generally doesn't preclude a COP setup.

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You didn't mention heat, someone else did. I made that point to illustrate that heat generally doesn't preclude a COP setup.

Gotcha..... :thumbsup:

Yes most of the issues and failures we noticed was due to poor internal design, insulators, and placing the high voltage circuit in the wrong areas with little to no isolation causing persistent flashover issues (some bikes at coil, some bikes at wire) at elevated combustion chamber pressures. This could also lead in some instances to damage in other circuits, especially if ground wires, input wires, run close to the high voltage wire.

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All YZF's have been COP since 2003. Most GM engines, and indeed, most modern automobiles and light trucks have generally gone to COP over the last 10 years or so. If heat were an issue, the underhood temps of the modern automobile would have killed off all of them by now.

A few observations of my own:

1) Manufacturers generally do not care to build products that vastly out live the warranty period. Its not cost effective, and most coils (COP) will last 30K miles no prob.

2) At least with GM, the highest performance models of the LS series motors still use CNP do they not?

3) I never meant to imply heat is the only killer of COP setups. But I do believe that run side by side in the exact same setup (i.e. two YZ450's one with COP and one with CNP) that the COP will fail first, even if it lives 10 years before doing so, just as a comparison.

What is the leading cause of an ignition coil falure?

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2) At least with GM, the highest performance models of the LS series motors still use CNP do they not?

What is the leading cause of an ignition coil falure?

As far as I know, no version of the current small block, including the LS7 and LS9 used in the ZO6 and ZR1 ever had anything other than COP. The engine design has no provision for anything resembling a distributor, and the only alternative would be either 4 or 8 separate coils mounted elsewhere and wired to the plugs. They might have done this, and they alone would know the reason, but I don't know for sure, since I haven't worked with them for quite a while, or paid that much attention. Either design is valid, however, and neither has an inherent disadvantage that cannot be overcome.

I don't know what the leading cause of coil failure in general would turn out to be, but my experience is that most of the time, it's either an internal sort or an open coil.

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