Did anybody burn igniter, using wrong COP?

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DreamV4

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article about AMPS for car ignition
" The current consumed by this ignition system is proportional to e engine speed. It rises from about 0.25 amp at 50 sparks per second to 2.5 amp at 500 sparks per second. "
 

02GF74

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OK, I'm not going to claim the be the expert here nor have read that article in detail but there are 2 things to consider, peak current and average current - the fact the current is said to increase in the article makes me believe it refers to the latter.

Below is picture of the current in an ignition coil. Being an inductor, it takes time to reach a peak (remember your post about resistance of coil and current) , then the ignition module still supplies power (max current possible is limited by coils resistance) in order that at every rpm, the spark has the same energy.

So the peak current is the same across rpm range but average current increases with the rpm.

Actually you can determine the peak current by measuring the coil resistance, from memory original coils are circa 3 ohm, COPs around 1.5 so that gives 4.6 and 5.3 Amps (using 14v as max voltage input).

Screenshot_20210821-080907.jpg
 

one2dmax

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From our experience there has been a correlation between CDI failures and non resistor cop installations. More people WITH cops (non-resistor type) have bought new CDI's from me (usually Ignitech) then those without them. Not all people who run non resistor cops have had CDI failures (yet). In fact the digital series of boxes (90-07) seem to be more durable. There are more of those bikes around but fewer of them have failed for any reason. Now, that could be because of the differences in the internals are better to begin with or it could be that the 85-89's are simply older. Within the last 2 years though I have sold a lot more CDI's to customers whos 90-07's have failed.

The Ignitec units allow for use with and without resistors with no damage to the unit. But it was desired for that from the start.

In the past the most common failures for the 90-07 bikes were the pickup coils. The 85-89 twin pickup to this day are far more durable and a part I sell far less often. The 85-89's CDI failures were not every usually complete. They simply would fire randomly with poor use at low RPM or poor output at high rpm. The 85-89's also have weaker sidestand relays and when they go bad the bike will crank all day long and not fire. Simply unplugging it allows the bypass.

One other thing of note,
The non-resistor COP's seem to alter the actuation timing of the vboost. I am not sure what causes that unless it's some sort of electrical "noise". It's not the same from bike to bike with some working normally and some vboost units not working at all after the swap.
 

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