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RaWarrior
Well-Known Member
If you have the Dyna, it doesn't matter which COPs you get. You MUST use in-line resistors or you WILL fry the box.
I'm sure there are some variations between brands of coil sticks, but none are as high as the stock coil packs.
Gannon (88vmx12) makes plug-and-play harnesses with resistors built in for this purpose.
Otherwise, most COPs are pretty similar. Mitsubishi or Denso seem to make about 99% of the ones out there. Some people report issues with the Mitsu's that went away when they switched to Denso, but I've been running Mitsu's (off a 2007 R6) for a good year now and have zero issues. No resistors, but I have the stock digital ignition.
I'm sure there are some variations between brands of coil sticks, but none are as high as the stock coil packs.
Gannon (88vmx12) makes plug-and-play harnesses with resistors built in for this purpose.
Otherwise, most COPs are pretty similar. Mitsubishi or Denso seem to make about 99% of the ones out there. Some people report issues with the Mitsu's that went away when they switched to Denso, but I've been running Mitsu's (off a 2007 R6) for a good year now and have zero issues. No resistors, but I have the stock digital ignition.
ninjaneer
Well-Known Member
generally speaking the highest resistance COP will be 1.5 ohms. i want to say denso, but don't quote me. if you didn't conclude from your research and already know, like RaWarrior says you're gonna need inline resistors because of the Dyna. if you don't want to bother with the math as well as the hunt, resort to Gannon's harnesses. I personally don't have them, but pics and reports suggest that they are high quality and workmanship. Also of note is you don't have to bother with hunting down the mating connectors to attach your signalling wires to your COPs. I believe 88vmx12 also provides the COPs themselves. If so, then your scot-free because I believe he will perform the necessary tolerance and compatibility checks before shipping them out to you. If you're like me who will find a sense of achievement and personal satisfaction in a complete DIY, then understand that your Dyna needs to see at least 3 ohms of resistance (COPs plus signaling wires) or risk placing the unit in "melt mode". Like RaWarrior says, the resistances of each COP vary slightly from batch to batch and from model to model, so if you're a demented perfectionist teetering on the edge of finding the last straw that doesn't break the camel's back, the exact inline resistor can't be determined until you measure your COPs. HOWEVER, you can safely assume that COPs are generally gonna fall within a certain range and purchase the resistor that will compensate the bottom of the range. Like RaWarrior says, most find success with Densos--look for the shorter models to simply installation (longer ones apparently work but are more of a PITA). Disclaimer: I'm speaking with just my understanding of the principle and have yet to complete the mod looking for the time to assemble the parts I have in hand.
thanks for the answer,but all that i know, i only want to know whits cop has the higest resistance (fit the vmax the bests).
i have got some from a gsxr 6oo but they will not work, only apx 0,07-0,11 ohm and that is to little.
i have got some from a gsxr 6oo but they will not work, only apx 0,07-0,11 ohm and that is to little.
RaWarrior
Well-Known Member
There's really no reason why those shouldn't work so long as the proper resistors are added. There really isn't a "best" COP for the vmax....all have significantly lower resistance, and all would need a resistor in your case.
The resistance of the coil doesn't really matter, as long as the equivalent resistance of the circuit is similar to the OEM coil. Doesn't matter if the extra resistance is in the coil, or in a separate resistor.
You can hunt around, but specs for COPs is gonna be tough to find. I'm sure you'll find some part and model numbers, but unless on another forum people have done as here (actually gone and measured them with a meter), I bet electrical data is going to be tough to come by.
The resistance of the coil doesn't really matter, as long as the equivalent resistance of the circuit is similar to the OEM coil. Doesn't matter if the extra resistance is in the coil, or in a separate resistor.
You can hunt around, but specs for COPs is gonna be tough to find. I'm sure you'll find some part and model numbers, but unless on another forum people have done as here (actually gone and measured them with a meter), I bet electrical data is going to be tough to come by.
alorio1
Well-Known Member
The coils I have are from a 1000 GSXR. they are the 4400 series coils from Denso. Mine are the long ones with inline resistor located in the wire harness, I don't know what the resistor value is but they are rather large in size and get fairly hot to the touch.
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RaWarrior
Well-Known Member
With resistors in series, you simply add the resistance (ohm) values. Req (equivalent resistance)= R1+R2
So no, it doesn't matter if the resistor has a higher ohm value than the coil...the ignition "sees" it as the sum of the two.
Parallel resistors have a more complicated method...
Req=
1
-----
(1/R1)+(1/R2)
Quick electrical lesson....ohm's law
V=iR
Voltage= i(current in amps)*R(resistance in ohms)
Voltage is a difference in electrical potential. If the R value goes up, the voltage does also, which at first doesn't make sense, but remember, voltage is a measure of difference. A higher resistance absorbs more energy, resulting in a bigger drop across it. Voltage is the potential to do work, where current actually does it. It's why a 110v wall outlet can/will kill you, but a 1M volt stun gun is essentially harmless. The wall outlet probably has 15 amps behind it, while the stun gun has only thousandths of an amp.
Move the equation around....i=V/R
If your resistance is too low (R is too small) and V doesn't change(say 14v), it means i goes up. More current, which in turn will fry your Dyna box.
So no, it doesn't matter if the resistor has a higher ohm value than the coil...the ignition "sees" it as the sum of the two.
Parallel resistors have a more complicated method...
Req=
1
-----
(1/R1)+(1/R2)
Quick electrical lesson....ohm's law
V=iR
Voltage= i(current in amps)*R(resistance in ohms)
Voltage is a difference in electrical potential. If the R value goes up, the voltage does also, which at first doesn't make sense, but remember, voltage is a measure of difference. A higher resistance absorbs more energy, resulting in a bigger drop across it. Voltage is the potential to do work, where current actually does it. It's why a 110v wall outlet can/will kill you, but a 1M volt stun gun is essentially harmless. The wall outlet probably has 15 amps behind it, while the stun gun has only thousandths of an amp.
Move the equation around....i=V/R
If your resistance is too low (R is too small) and V doesn't change(say 14v), it means i goes up. More current, which in turn will fry your Dyna box.
i got some COPs and harnesses from gannon and they were about 4.1-4.2 resistance on a mulitmeter where as stock was about 3.6. they ran fine but the bike took like 25s to start up with them. he has since sent me new ones to try but just something to keep in mind (i'm running dyna 3000 - curve 2)
sdt354
Well-Known Member
pm sent
satariel666
Well-Known Member
Why would those first not work?
It does matter - try to find the donnor manual and its electrical diagram.
sdt354
Well-Known Member
got an OEM harness somewhere. Will post a pic-off to find it.
Steve-o
Steve-o
