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plug caps and coils


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I have a problem with my XJ 750. The plugs are all totally sooted up in 100 miles.

I got to thinking that it is the coils. The manual says that I should get about 13K ohms across the secondary winding (plugs 1&4 2&3). I am gettng 22K ohms but 13 without the caps.

so my question is, although the diagram in the manual shows with caps, should I measure with or with out them?

I am getting 4K ohms through each cap alone. Should I try to get non-resistored caps or are my coils breaking down or am I barking up the wrong tree?

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I always read it as without caps.

caps come in two flavours 5 ohms and 10 ihms. the 10 ohms give a weaker but longer spark, with the 5k strong but short, depends on the bike specs really.

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Thanks Drewpy. Looks like my problem isnt my coils then. The HT leads were heavily oxidised where the cap screwed in. Cutting them back did help a little.

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