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DYNATEC HT Coils - Plug Leads - Plug Caps, opinions on compatible set ?

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400 Cafe Racer:
Hi Guys,

Just in the process of engine rebuild and checking other items before the refit.

The PO has DS Electronic Ignition and the Dynatec Coils fitted with carbon trace HT leads, not copper wire leads (see photo) these are then connected to 5Kohm plug caps. I was interested to check the HT cable resistance seperately.
All plug caps come in at 5Kohms, but the Ht leads measured along the disconnected cables vary, No1 = 12.4Kohm intermittent reading, No2 = 18Kohm solid reading, No3 = 12Kohm solid reading, No4 = 17Kohm solid reading.

I have my misgivings about carbon impregnated cotton plug leads, which can break the carbon chain if the lead is stretched, I'm thinking this could be the reason for the intermittent reading on No1.

Spark Plugs are NGK D8EA

I am interested to hear your views and experiences. ;)

Thanks

Dennis

K2-K6:
As you note,  there's very divided opinion of carbon type leads. I really like them and have used them widely for many years on cars but not experienced on these bikes directly. 

Also can't see a specific problem used on your bike and it's perhaps been running on them some time.

Agree that the inconsistent #1 lead is quite probably causing you difficulty, can you swap with #4 or replace to test  ?

400 Cafe Racer:
Thanks K2 - K6,

As you say,opinion seems to be divided. I will probably fit new leads to hopefully even out the resistance readings more.

Do we know what specification of the original leads and caps were please. ?

Would this same combination suit the Dynatec Coils ?

Thanks for your comments.

Dennis :)

K2-K6:
Ordinary manual specification is very low resistance leads with 5 ohm plug caps along with non resistance plugs.

"Would this same combination suit the Dynatec Coils ?" That's certainly a more complex question though, with Dynatec seeming happy to use different leads etc to manufacture of motorcycle specification. 

You've also got interaction with the DS switching which I doubt has a parallel technical parity with the points originally installed.

Given the system specification as it stands,  I'd replace the leads with same type and aim for maximum of 15 ohm for each lead, cap and plug line.

McCabe-Thiele (Ted):
My Dynatec full system came with carbon leads so that's what I have fitted.

In your situation I would make up a set of copper wired leads as in many ways I'm old school I like the good conection you can see with copper particularly at the ends to coil & plug cap. It's not as if you have a bike radio to consider as regards interference? lol

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