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Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Thu Sep 15, 2011 10:38 pm
by Variablevalves suck
Parus, thanks for the link to the Bosh unit, it got me thinking and i had a snoop around their site and came up with a few answers to why the cops work with a series loom that only supplies 6v at the coil.
If you take a look at the pdf for one of their caps (all very similar) it shows a working voltage range of 6v to 24v, the difference between voltages changes the dwell for the unit.
http://www.bosch-motorsport.de/en-US/li ... 227531.pdf
I would have thought the micro squirt would have worked using this type of wiring.
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Sat Sep 17, 2011 9:10 pm
by cajun
2006 R1 coils fit without sticking over the valve cover.
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Sat Sep 17, 2011 9:29 pm
by Variablevalves suck
Do you use a set? could you post the lenght?
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Sat Sep 17, 2011 9:35 pm
by Drunkn Munky
Slightly off topic here but when i fitted COP's to my RVF i never thought they would burn out the stock CDI, i did have an ignitech yet i didnt see any settings in the software for them. Is it different for V4's or was i just lucky that i had a ignitech fitted?
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Sat Sep 17, 2011 10:35 pm
by Variablevalves suck
Hi mate, it is down to basic physics.
In an electrical circuit you have volts = 12 , amps =? and ohms (resistance at coil)
V volts=I(amps) X R(ohms)
So if your standard coil is 3 ohms you get 12v/3ohm=4amps in the circuit.
If you connect your cops in series you would simply add the ohms for each cop so 1.5 + 1.5=3ohm
back to the V=I x R you get the same 4 amps
BUT if you connect cops in parallel - 1 and 4, 2 and 3 as your original ht caps you use a different equation
1/R total= 1/R1+1/R2
1/R total=1/1.5ohm+ 1/1.5ohm
1/R total=0.666+0.6666
1/R total=1.33333
R total=1/1.33333
R total=0.75ohms so instead of 3 ohms (series) you got 0.75ohms
back to V=I X R and 12v/0.75 ohms = 16 amps
You will have 16 amps in the circuit instead of 4amps and this will cause problems.
BUT running the cops in series will work as a voltage divider so giving 6v at each cop. Understand?

Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Sun Sep 18, 2011 1:45 am
by cajun
Variablevalves suck wrote:Do you use a set? could you post the lenght?
Yes, I use the same ones as Greggo did in his thread. I will have to get some measurements tomorrow.
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Mon Sep 19, 2011 9:25 pm
by PARUS
Thank you for responses to all...
Parus, thanks for the link to the Bosh unit, it got me thinking and i had a snoop around their site and came up with a few answers to why the cops work with a series loom that only supplies 6v at the coil.
If you take a look at the pdf for one of their caps (all very similar) it shows a working voltage range of 6v to 24v, the difference between voltages changes the dwell for the unit.
http://www.bosch-motorsport.de/en-US/li ... 227531.pdf
I would have thought the micro squirt would have worked using this type of wiring.
As I see from this diagram supplied voltage - 6 to 16.5 V. Microsquirt V3.0 board will be supply only logic control for ignition and external igniter like Bosch or other will be required.
2006 R1 coils fit without sticking over the valve cover.
Could you upload the picture ? I like to check difference. I have connectors for CBR600 plug and if there is no significant changes I will use CBR600 COPs.
Slightly off topic here but when i fitted COP's to my RVF i never thought they would burn out the stock CDI, i did have an ignitech yet i didnt see any settings in the software for them. Is it different for V4's or was i just lucky that i had a ignitech fitted?
All Ignitech do - just control spark advance and adjust it depend on uploaded map. I have spoken with Rick and he told that dwell time is 3.0 - 3.1msec. Same one I have with Microsquirt and stock HT coils. But I have tried 3.4 or ever 4.0 and spark was better without overheating the coils.
Hi mate, it is down to basic physics.
In an electrical circuit you have volts = 12 , amps =? and ohms (resistance at coil)
V volts=I(amps) X R(ohms)
So if your standard coil is 3 ohms you get 12v/3ohm=4amps in the circuit.
If you connect your cops in series you would simply add the ohms for each cop so 1.5 + 1.5=3ohm
back to the V=I x R you get the same 4 amps
BUT if you connect cops in parallel - 1 and 4, 2 and 3 as your original ht caps you use a different equation
1/R total= 1/R1+1/R2
1/R total=1/1.5ohm+ 1/1.5ohm
1/R total=0.666+0.6666
1/R total=1.33333
R total=1/1.33333
R total=0.75ohms so instead of 3 ohms (series) you got 0.75ohms
back to V=I X R and 12v/0.75 ohms = 16 amps
You will have 16 amps in the circuit instead of 4amps and this will cause problems.
BUT running the cops in series will work as a voltage divider so giving 6v at each cop. Understand?
That's right (in case you have 1.5 ohms primary coils resistance). I would like to add some more. You do not mention dwell time.
As you can see from CBR600 wiring each coil drives directly, not by pair as we have in CBR400. So, let calculate dwell for both at 12000 RPM, both of these 4-stroke, 4-cylinder.
CBR600 - 12000rpm/60 sec = 200 revs/sec = 2spark per rev * 200 revs\sec = 400 sparks per sec.
= 1000 millisec / 400 spark per sec = 2.5msec (This max dwell time).
CBR400 = ...bla...bla...bla... = 200 sparks per sec. As far as we have wasted spark - one coil spark two coils (1-4 or 2-3) we need to charge coil twice and in this case time will be twice less = 1.25msec
So, because we have less resistance coils for CBR600 during this 1.25msec we got better saturation with COP than with stock coils.
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Tue Sep 20, 2011 9:31 am
by PARUS
Sorry, I'm stupid idiot. As far as cylinder firing order will be 1-3-4-2, so coils spark only ones per cylinder rotation. So, time need to be multiple by 2.
CBR600 - 5msec,
CBR400 - 2.5 msec.
But we also need to consider spark duration time - which is about from 1-2 msec.
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Mon Oct 24, 2011 9:55 pm
by PARUS
Re: COP(coils-on-plug). Which ones can be fitted?
Posted: Mon Oct 31, 2011 1:00 pm
by leopard_pagan
also see this thread about the same subject...
viewtopic.php?f=10&t=30676
i am doing this the other way round.. fitting COPs to a 1992 CBR600 lump with COPs from a CBR6 2000+
