Birdoprey's COP (Coils Over Plugs) Mod

[MaxRyan]

I agree with the above and the .5 ohm resistor, it will only drop half the voltage using a resistor equal to that of the primary winding. Here is the second problem that i can foresee, power is equal to current x voltage or voltage squared/ resistance. So the power rating of the resistor you will need is (3.23x3.23)/0.5 = 20.8 watts, That is one fairly large resistor and i doubt you will find a .5 ohm in that size. You could use 2 one ohm in parallel though.

 

[RagingMain]

Here is one
http://www.mouser.com/Search/Refine...294646487+4294575790&Keyword=284-HS10&FS=True
I didnt like this resistor because it has a tolerance of 5%. I wanted something a little bit tighter biglaugh, and it is expensive for 4 of them, so I decided to go with a 1ohm resistor so the power rating would be half as much, just around 10 so I chose this one
http://www.mouser.com/Search/Refine...294619412+4294571600&Keyword=284-HS15&FS=True
It is a 1% tolerance, 15 watts and only 1ohm. You could put two of these in parallel and get your .5ohm and still have the power rating needed. Plus I like them because they are aluminum and can be mounted to the bike to help with heat issues.

 

[MaxRyan]

Here is one
http://www.mouser.com/Search/Refine...294646487+4294575790&Keyword=284-HS10&FS=True
I didnt like this resistor because it has a tolerance of 5%. I wanted something a little bit tighter biglaugh, and it is expensive for 4 of them, so I decided to go with a 1ohm resistor so the power rating would be half as much, just around 10 so I chose this one
http://www.mouser.com/Search/Refine...294619412+4294571600&Keyword=284-HS15&FS=True
It is a 1% tolerance, 15 watts and only 1ohm. You could put two of these in parallel and get your .5ohm and still have the power rating needed. Plus I like them because they are aluminum and can be mounted to the bike to help with heat issues.

Yup those would work, Most likely two 15 watt would be much smaller than one 100 watt as well.

 

[vmax626]

Here is one
http://www.mouser.com/Search/Refine...294646487+4294575790&Keyword=284-HS10&FS=True
I didnt like this resistor because it has a tolerance of 5%. I wanted something a little bit tighter biglaugh, and it is expensive for 4 of them, so I decided to go with a 1ohm resistor so the power rating would be half as much, just around 10 so I chose this one
http://www.mouser.com/Search/Refine...294619412+4294571600&Keyword=284-HS15&FS=True
It is a 1% tolerance, 15 watts and only 1ohm. You could put two of these in parallel and get your .5ohm and still have the power rating needed. Plus I like them because they are aluminum and can be mounted to the bike to help with heat issues.

These resistors, are they run parallel (side by side) before the coil on the hot lead ?? so you used 8 of them right ? <<Dave>>

 

[RagingMain]

These resistors, are they run parallel (side by side) before the coil on the hot lead ?? so you used * of them right ? <<Dave>>

You can do that. As soon as I get around to it I am just going to use a single 1ohm on the hot lead as close to the coil as possible. This will lower the current even more and deliver adequate voltage. Makes for an easier and cleaner installation

 

[vmax626]

You can do that. As soon as I get around to it I am just going to use a single 1ohm on the hot lead as close to the coil as possible. This will lower the current even more and deliver adequate voltage. Makes for an easier and cleaner installation

You said that they are run parallel but shouldn`t they be run in series
(one in front of the other )/ to cut down the ohms ?:confused2: The pictures of them I have seen look like they are run inline:ummm:

 

[maleko89]

No, resistors added in series increase Ohms. You add values of resistors in series. Formula for parallel is 1 / R = 1 / R1 + 1 / R2 + 1 / R3 +... .

So, if R1 is 8 Ohms, R2 is 8 Ohms and R3 is 4 Ohms you get

1/R = 1/8 + 1/8 + 1/4 = 1/2. So, R = 2 Ohms. in series, you would get 20 Ohms.

 

[vmax626]

No, resistors added in series increase Ohms. You add values of resistors in series. Formula for parallel is 1 / R = 1 / R1 + 1 / R2 + 1 / R3 +... .

So, if R1 is 8 Ohms, R2 is 8 Ohms and R3 is 4 Ohms you get

1/R = 1/8 + 1/8 + 1/4 = 1/2. So, R = 2 Ohms. in series, you would get 20 Ohms.

sorry my mistake , boy 3 years of electronics and a guitar tech I can`t believe I said that !musta been the devil talkin.:ummm:

 

[RagingMain]

No, resistors added in series increase Ohms. You add values of resistors in series. Formula for parallel is 1 / R = 1 / R1 + 1 / R2 + 1 / R3 +... .

So, if R1 is 8 Ohms, R2 is 8 Ohms and R3 is 4 Ohms you get

1/R = 1/8 + 1/8 + 1/4 = 1/2. So, R = 2 Ohms(for parallel). in series, you would get 20 Ohms.

Exactly correct.
For this particular application I believe that one 1ohm resistor spliced inline with the COP on the hot side will do the trick but I dont know yet for sure. The math says it will work (theroy) but sometimes practical application is a whole different animal.

 

[vmax626]

Exactly correct.
For this particular application I believe that one 1ohm resistor spliced inline with the COP on the hot side will do the trick but I dont know yet for sure. The math says it will work (theroy) but sometimes practical application is a whole different animal.

What bike was it that you got the COP`s from ??
<<Dave>>

 

[vmax626]

Thanks Danny for showing the ease of install. I've not had the time, and i could not have done as well either. You've also had the same results i've seen.
For those that have questions, here is a link of a post of mine with more indepth info. There is also a link(on that link!) that has a vid and even more info(quite long though).
http://www.vmaxforum.net/showthread.php?t=5656

In a nutshell, this mod is:
A performance mod. Dunno about peak hp, but definate gains down low with better response, quicker startup, etc. MPG gains will follow sometime later.
A cheap replacement alternative to the crack/failure prone stock coil/wire/boot setup. Stk coils run around $70 EACH. Then you have wires and boots. If you do it yourself, one can swap to the COPs for around $50-60. Possible to score them a lil cheaper, but not often. MUCH cheaper than aftermarket alternatives. And if you do happen to have one or all cop's fail(i've never seen one fail), all you need to do is replace the cops(sets of just cops can be had for $20-35shipped). Pick up a set and throw then under your seat...
A showy mod for that "COOL" factor. Pretty slick having COP's on a dinasaur!
A COOL way to shed some weight AND make more room on your bike. Mr. Max has never been refered to as "lithe" or "un-cluttered"...!!! The COP's are lighter/smaller and less complicated than the factory setup or even the aftermarket alternatives.

Are those 50 to 60 bucks each ??? or a set of 4 ??:ummm:
<<Dave>>

 

[joelyons50023]

Set of 4

 

[tvmax]

You need the resistor because you are running the aftermarket ignition box correct? Do you need it if you are running the stock box? Has anyone been runnig the stock box for a while with COP's?

Thanks
Jim

 

[Thevmaxrider]

You need the resistor because you are running the aftermarket ignition box correct? Do you need it if you are running the stock box? Has anyone been runnig the stock box for a while with COP's?

Thanks
Jim

Thanks for asking this question!!! I was just going to ask the same thing. From what I can glean it seems that the stock CDI box is holding up alright, but the Dyna3000 boxes are frying. Would be nice to know before I find myself alongside the road LOL.

 

[vmax626]

Thanks for asking this question!!! I was just going to ask the same thing. From what I can glean it seems that the stock CDI box is holding up alright, but the Dyna3000 boxes are frying. Would be nice to know before I find myself alongside the road LOL.

I was worried about that too because I am running the stock ignition box and I don`t want to get stranded in the middle of bumf#*k eygupt.:bang head:.
<<Dave>>

 

[vmax626]

Set of 4

Are they that cheap at the dealer ? We used to have a motorcycle salvage out here where you could buy that stuff easily but it turned into Bert`s Mega Mall. It`s a humongous dealership now.

 

[dannymax]

Are they that cheap at the dealer ? We used to have a motorcycle salvage out here where you could buy that stuff easily but it turned into Bert`s Mega Mall. It`s a humongous dealership now.

I doubt that you could get them from a dealer for that price, but there are usually a few sets on e bay....check Birdoprey's list for compatibility, it's in this thread.

 

[RagingMain]

I was worried about that too because I am running the stock ignition box and I don`t want to get stranded in the middle of bumf#*k eygupt.:bang head:.
<<Dave>>

As far as I can tell right now the stock box is not having a problem with it at all. It is my Dynas that I have been frying.

Thanks for asking this question!!! I was just going to ask the same thing. From what I can glean it seems that the stock CDI box is holding up alright, but the Dyna3000 boxes are frying. Would be nice to know before I find myself alongside the road LOL.

Just so you guys know our stockers are NOT CDI, that is a newer technology than our Dinosaurs do not have. Ours are TCI, transistor controlled NOT capacitive discharge.

 

[Birdoprey]

Guys,

There are several that have run the COP's with the stk ignition that have clocked over 1000 mi(personally i've logged over 1500mi and i believe Naughty has over 2500 or prolly more by now) with out any issues at all. There have been 3(i believe thats the case) that have run Dyna 3000's with the COP's and i believe all three have had issues of some kind with Fargo taking the lead with failures.
I looked quite a bit into a way to get the COPs to work with the Dyna with out any success. The only thing i came up with was trying the resistors like Fargo is gonna try. I don't have a Dyna so its not something i can try out.

 

[vmax626]

Guys,

There are several that have run the COP's with the stk ignition that have clocked over 1000 mi(personally i've logged over 1500mi and i believe Naughty has over 2500 or prolly more by now) with out any issues at all. There have been 3(i believe thats the case) that have run Dyna 3000's with the COP's and i believe all three have had issues of some kind with Fargo taking the lead with failures.
I looked quite a bit into a way to get the COPs to work with the Dyna with out any success. The only thing i came up with was trying the resistors like Fargo is gonna try. I don't have a Dyna so its not something i can try out.

If I can find them, Could you tell me the ones that would work best with my 2000 max (taken from which bike model, make and year ) there are a couple repair shops(small ones) that have salvaged bikes in the back and they usually sell parts cheap.

<<Dave>>