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Sparky!!!
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Discussion Starter #1
thanks to Dariv (for the TCI link) and my friend Vince (for offering me a possible VN700), I am wanting to learn more about our ignition coils. More specifically how they work, and what the different resistant ratings mean. What else do I need to look at when upgrading the coils from stock to get a hotter more prercise spark?

I know that just adding bigger coils isn't going to do anything, but I am thinking along the lines of coils, pick up coils, and the igniter box. I have the last two figured out for now.
 

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MANIC MECHANIC
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spark voltage is induced current caused by the collapsing magnetic field from the primary windings. the more secondary windings the more voltage.
 

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A higher coil output voltage translates into stronger spark only when it is not achieved at the cost of reduced spark current. And that is exactly what happens if you just increase the number of turns in the coil secondary winding. Increasing the number of turns also means higher DC resistance, which further reduces the current. A better measure to compare coils would be the amount of energy they deliver per spark, but do the manufacturers tell that?

With the inductive ignition you could expect that the more energy can be stored to the magnetic field of the coil, the more powerful spark you get. This information is available for some coils. Of course there are also many other factors (which all I am not aware of) affecting here, so in the end you just believe (or not) the assertions of the manufacturer.
 

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Sparky!!!
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Discussion Starter #5
i think i am fallowing... so in other words... nothing in the spec sheets make on coil better than aanother because they don't do the right tests on them. hmmm...

so say I am trying to build a stroker engine around the vulcan platform, would I even need to worry about hotter spark?
 

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so say I am trying to build a stroker engine around the vulcan platform, would I even need to worry about hotter spark?
I don't think you need a hotter spark, but if you increase the compression, then more voltage is needed before the spark ignites. I believe the standard coil can handle this, but someone else might say that you need a 'power' coil.

If you are into racing, then you use all possible ways to get the best performance, but we are not talking racing - are we?

And.. the scenario of stroking the Vulcan engine is just hypothetical?
 

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thanks to Dariv (for the TCI link) and my friend Vince (for offering me a possible VN700), I am wanting to learn more about our ignition coils. More specifically how they work, and what the different resistant ratings mean. What else do I need to look at when upgrading the coils from stock to get a hotter more prercise spark?

I know that just adding bigger coils isn't going to do anything, but I am thinking along the lines of coils, pick up coils, and the igniter box. I have the last two figured out for now.
Are you staying with the TCI ignition, or switching to a CDI setup, or something else??
 

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Sparky!!!
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Discussion Starter #8
I don't think you need a hotter spark, but if you increase the compression, then more voltage is needed before the spark ignites. I believe the standard coil can handle this, but someone else might say that you need a 'power' coil.

If you are into racing, then you use all possible ways to get the best performance, but we are not talking racing - are we?

And.. the scenario of stroking the Vulcan engine is just hypothetical?
I might be talking racing... not sure yet, I am picking up a VN700 next summer that I am thinking of doing som crazy things to... Taking it to the drag track once in a while is on my list.
As far as stroking the engine, If I can figure out all the necessary parts, then yes its going to happen. but right now its all hypothetical... after I get back from my deployment, I am going to have a lot of time on my hands for about a year or so.
Are you staying with the TCI ignition, or switching to a CDI setup, or something else??
I am going to be getting the ignitech ignition box you are looking at... I am going to buy it from a distributor on my CX500 forum, because he can get them to me cheaper sine he does a group buy every three months...
 

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I might be talking racing...
In that case you can disregard my opinions. For me it is enough that the engine runs well. I couldn't even tell the difference if the engine had a little more or less power.
 

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...I am going to be getting the ignitech ignition box you are looking at...
There are several unused I/O points on that unit..... for example, the servo input/output, fuel pump output, shift light, and so on. I was trying to think of ways to utilize them. Maybe set the shift light output to signal at over 500 RPM and use that output to drive a relay that would only be on when the bike is running..... for turning on lighting or auxiliary equipment.
Any ideas?
 

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Sparky!!!
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Discussion Starter #12
I am looking into the unit you are getting, but am being steered tword a differnt CDI box by the same company.

For lighting and such, run it off of the fuel pump line. I was thinking of getting a throttle tube with a TPS (Throttle Position Sensor) and using this to help curve the advance (not sure if it would work still in the dream state), and I don't know why we would need the servo since it is used as a choke, and would need more sensors to feed it.
 

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Are the stock coils a single fire, or dual fire? I'm thinking they are the single fire because they only fire one cylinder unlike the Harley that fires two separate cylinders.
Am I correct in my thinking? The reason I am asking, is because I'm going to convert to an aftermarket coil with more spark and go with 9MM wires.
 

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Sparky!!!
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Discussion Starter #14
they are single fire, bt you need to watch out when trying to go with a larger coil than what is stock on the bike.. our stock TCI Box can't handle more than what is already on there... hence looking into other ignition control modules.
 

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...For lighting and such, run it off of the fuel pump line....
Does a motorcycle fuel pump work different from a car? On my car, when you turn the key from off to on, the pump runs for a couple seconds, then shuts off till you crank the motor.......don't know if I would want the lights to come on before the engine was running...
 

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I know there are different resistance ratings on the coils so as to not overload the TCI unit. I will have to research it, but Dennis Kirk offers several types of coils for single fire type systems with 2 different ratings to match up to either a CDI type or TCI type unit.
 

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Sparky!!!
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Discussion Starter #17
Does a motorcycle fuel pump work different from a car? On my car, when you turn the key from off to on, the pump runs for a couple seconds, then shuts off till you crank the motor.......don't know if I would want the lights to come on before the engine was running...
They work the same... but the reason the fuel pump shuts off after a couple of seconds is because as soon as the desired fuel presure is met the fuel pump relay switches off power to the fuel pump.. as soon as you start the engine, the fuel pump runs continuously. I am sure there would be a way to rig up the relay to come on after the engine is running... I will think more in depth on this
 

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...I am sure there would be a way to rig up the relay to come on after the engine is running... I will think more in depth on this
Since I'm converting everything over to LED's anyway, I don't think I need to complicate the circuit anymore. At this point I'm thinking of using a SPDT off the high/low switch to feed the lights full bat. power. Maybe feed the low beam via the NC contact and have the 'high' switch position energize the relay for high beam, or something like that...
 

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Sparky!!!
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Discussion Starter #19
that would work... I don't think we want to use the fuel pump wire to trigger a relay for lighting.. maybe for the accessory relay.??
 
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