Cops Mod questions

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I got my Kit from gannon... about to install. So the rear coils are NOT crossed? and the Front are.... What are the numbers for each cylinder?

sitting on the bike the cylinders are numbered as follows

2 4
1 3


yes, the front ones (2 & 4) are crossed and the rear ones (1 & 3) are not.
 
sorry for hijacking the thread, but didn't want to start another one, got just one question...

we all know how to convert 4 coil-4 cylinder system into COPs, but I'm having difficulties with an R1, or any inline 4 engine fired with only 2 coils in this instance, to convert such to COPS

in other words, converting 2coil-4cylinder system into 4 COPs, how to????

Started working on one and yes it will work... or atleast it will on the Kawasaki ZL900 that we are woring on.

Gannon
 
Try to wire them in series - not pararell...on the side note by joining the COP's in parallel you have divided the resistance by two...you may accidently toasted
the TCI...but for the SHOP its not a bidg deal, ey ;)
 
Ok so i have tried .022, .026, and .030 gaps and i don't feel any difference. I still have to use the choke every time to start cold... Its not stumbling nearly as much but overall not to impressed for the amount of money spent. Am i missing something?
 
Ok so i have tried .022, .026, and .030 gaps and i don't feel any difference. I still have to use the choke every time to start cold... Its not stumbling nearly as much but overall not to impressed for the amount of money spent. Am i missing something?


I want to throw in a quick opinion here,,,,
The only thing you're missing is that with or without COP's, if your bike is starting and running great when cold, without the choke, then you are jetted too rich on our idle jets.

A carbureted engine should be a little 'cold blooded' when first started. If it runs great with no choke when cold, what do you suppose it will run like when warm? Too rich,,,,, and wayyyyyyyyyy too rich when getting hot.

I have the COP mod. My bike runs great when warmed up. Runs great when cold, WITH the choke on. OK?

Vinnie
 
Usually with dual-plug coils there's an extra wire going into the coil pack. Our single plug vmax coils have two, a ground and a trigger wire. Dual plug ones usually have three....a ground and a trigger for each side.

The vmax fires the coil by grounding it(always has +12v whenever key is on), but some bikes fire it by sending a quick pulse of power to an always-grounded coil.
 
Usually with dual-plug coils there's an extra wire going into the coil pack. Our single plug vmax coils have two, a ground and a trigger wire. Dual plug ones usually have three....a ground and a trigger for each side.

The vmax fires the coil by grounding it(always has +12v whenever key is on), but some bikes fire it by sending a quick pulse of power to an always-grounded coil.

The Kawasaki that we are working on doing a coil conversion has 2 wires. Same set up as his. The cylinder that is on the same coil as the other, also fires when it is on the exhaust stroke etc. They are pretty easy to figure out! :clapping:
 
Are these wiring harnesses with the inline resistors still available? I have been searching this forum and seem to find conflicting stories. I bought a set of COP's for my '89 and need the wiring kit (harnesses).
 
Are these wiring harnesses with the inline resistors still available? I have been searching this forum and seem to find conflicting stories. I bought a set of COP's for my '89 and need the wiring kit (harnesses).

they are but without the resistors. you run the risk of cdi box damge with out em....however..there are folks here that have run them 4 years without issue.....so its a crapshoot i guess.

contact 88vmx12 if you need any info.
 
sorry for hijacking the thread, but didn't want to start another one, got just one question...

we all know how to convert 4 coil-4 cylinder system into COPs, but I'm having difficulties with an R1, or any inline 4 engine fired with only 2 coils in this instance, to convert such to COPS

in other words, converting 2coil-4cylinder system into 4 COPs, how to????


It is top secret! LOL

G
 
If the resistance if the original coil is the same as a COP, then run the COPs in parallel and put a ballast resistor half the resistance value of one COP in line between the ignition and the COPS. This is because 2 COPs in parallel will be half the resistance so you need the ballast to make up the other half. The ignition will then 'see' a resistance value equal to that of one COP/coil.
If the coil resistance is more than one COP or less but greater than half, you will need to work out what the resistance of the 2 COPs in parallel comes to and use a ballast resistor to make up the difference.
If ithe coil is less or equal to half the resistance of a COP, then use the COPs without ballast resistors.
The COPS then go on the cylinders the coil would have supplied (usually 1 & 4 and 2 & 3).
 
Now you got me lost there Colin... Each coil is separate due firing order. No parallel on them
 
Assuming it is a non cross plane crankshaft (i.e. two pistons at t.d.c and two at b.d.c) then the coils will fire on every rotation of the crankshaft.

Two coils are needed for each pair of pistons.

Of the paired pistons, one will be on the firing stroke the other on the exhaust stroke which receives a wasted spark.

What Mr Wolfmax is saying that it is prudent that the e.c.u. 'sees' the same resistance that two c.o.p.'s have that would normally be present if the original single coil was being used to generate the spark.

For example; if the original coil had a primary resistance of 2 ohms and the c.o.p.'s had the same resistance then when connected in parallel the the resistance 'seen' by the e.c.u. would be 1 ohm i.e. half of what is normally present.
A ballast resistor would be required to make up the difference.
 
You know when you want to say somthing but the words just run away with themselves...

Thanks MM for saying it so succinclty.

Cheers
 

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