Spark Plug Resistance

Sowiuk1

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So I just installed a PMA CDI ignition system onto the XS. However I’m not getting any spark.
I’ve tested the spark plugs and they gave continuity but no resistance. Upon research I should have around 5000 OHM resistance through the spark plug whoever I only have 3 OHM. (I made sure the multimeter was on correct setting)
Both spark plugs are new and are both the same. Is it just a coincidence that they are both dud or is this how they’re meant to be.

Thanks again for any help.
 

Raymond

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You need to have that 5 kΩ resistance, which can be achieved by using resistor plug caps, which are standard on XSs, or by using resistor plugs, designated by R, for example BPR7ES is same as BP7ES but has built-in resistor.

I learned this when I inadvertently replaced resistor plug caps with ones that had no resistance - shut down the Boyer Bransden ignition.

There can be other reasons for no spark but I'd tackle this issue first.

EDIT - just noticed you're from Alton, I lived there for sixteen years, nice little town.
 

Sowiuk1

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You need to have that 5 kΩ resistance, which can be achieved by using resistor plug caps, which are standard on XSs, or by using resistor plugs, designated by R, for example BPR7ES is same as BP7ES but has built-in resistor.

I learned this when I inadvertently replaced resistor plug caps with ones that had no resistance - shut down the Boyer Bransden ignition.

There can be other reasons for no spark but I'd tackle this issue first.

EDIT - just noticed you're from Alton, I lived there for sixteen years, nice little town.
Awesome thank you for the information I’ve just been to euros and got the BPR7ES spark plugs and will try those.
Yeah I’ve lived in Alton also since 2005 it’s a nice town slowly expanding unfortunately.
 

bosco659

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You need to have that 5 kΩ resistance, which can be achieved by using resistor plug caps, which are standard on XSs, or by using resistor plugs, designated by R, for example BPR7ES is same as BP7ES but has built-in resistor.

I learned this when I inadvertently replaced resistor plug caps with ones that had no resistance - shut down the Boyer Bransden ignition.

There can be other reasons for no spark but I'd tackle this issue first.

EDIT - just noticed you're from Alton, I lived there for sixteen years, nice little town.
I‘m running a Pamco on my ‘76. I’m using resistor BPR7EIX plugs but noticed the other day that I have resistor caps as well. On another thread it was suggested this wasn’t a good thing having 5K resistance on both plugs and caps. Should I swap the caps to a non resistor type or just leave it as is? Seems to run fine this way.
 
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