Resistor plugs and caps.

The MKII bike and Wassell EI are what I have and all runs fine using stock coils with Champion N7YC plugs, copper core non supressed HT leads with non-resistor caps. Recently installed voltage monitor/oil pressure warning LED that states to use suppression ignition to prevent interference with its circuitry, so now running 5kOhm caps. No noticeable difference in running. I have also run upto 10kOhm caps (Lucas hard bakelite type) with same leads/plugs and no issues.
 
Thanks guys. I tested the lead, only one, with the cap on. I'll grab a beer and head out to the garage and investigate further this evening.
 
The other lead measured 2600 ohms. Caps are not removable. It says 'PACKARD high performance silicone suppression cable - USA' on the side. 20230421_232228.jpg
 
I have the voltage / oil pressure warning LED system like Tornado. Will be installing that soon.
 
Saber said:
The other lead measured 2600 ohms. Caps are not removable. It says 'PACKARD high performance silicone suppression cable - USA' on the side. View attachment 105965
Click to expand...
OK, that clears that part up. If you want to use those wires, then you should not use resistor plugs. However, as long as the plug gap is correct and you're not overly high compression, you'll be fine with the combination.
 
Saber said:
'PACKARD high performance silicone suppression cable - USA'
Click to expand...
Best got rid of, these carbon fibre cored leads cannot handle the vibration from a rubber mounted engine at one end and a fixed coil at the other. They will start to give intermittent misfires before failing completely. Have the T shirt and replaced them with solid copper cored HT leads.
 
kommando said:
Best got rid of, these carbon fibre cored leads cannot handle the vibration from a rubber mounted engine at one end and a fixed coil at the other. They will start to give intermittent misfires before failing completely. Have the T shirt and replaced them with solid copper cored HT leads.
Click to expand...
I agree and said so at post #80.

Also, people mention that I said I've tested from 0-10k ohms but leave out that that are caveats. The test was on a Combat so that compression is OK, higher, probably not. The plug gap was 0.025" carefully set. IMHO 0.028" is too much especially with 10k ohms of suppression and higher compression. The manufacturers of the ignition systems who specify that suppression be used say 5k ohms either in the plugs or caps. Why try to outthink the guy who designed the ignition?

Wassell is selling 10k caps. Wassell sells car parts as well as motorcycle parts and those caps are correct for some vintage British cars - that's why I don't stock them - I don't sell car parts.

I use resistor plugs only.

I would not like to be stranded by carbon plug wires so I won't use them.
 
This is a picture of the coil end of the lead. I presume the black center verifies it is a carbon fiber core? I 'won' these at a norton rally so i just replaced what was on the bike. I dug the old ones out and see they are copper core. Measured 10 ohms resistance. So I will put the old ones back on with the 5k Autolite APP 63 plugs and carry on to the next thing. Thanks for the education friends.

20230423_091114.jpg
 
L.A.B. said:
If it's the Pazon Sure-Fire then resistor plugs/caps/wires are not required and only a recommendation.
"We recommend fitting NGK 5K resistor (suppressor) type plug caps (or similar good quality make), but you can also fit non-resistor caps."

Pazon Smart-Fire and Altair both need resistors:
"This system is designed to work only with the special digital ignition coil provided with the system. A 5K resistor plug cap as supplied with the system should be fitted to the h.t. lead. Alternatively, a resistor spark plug can be used. A resistor plug & resistor cap can be used together, although it is not necessary to use both. Attempting to run the system without a resistor type cap or plug will result in excessive radio frequency interference (r.f.i.), which may cause bad running, misfiring and loss of ignition. For reliability, copper or steel cored h.t. lead should be used, we do not recommend using carbon fibre lead."
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I am more confused than ever now.

"....this system isdesigned to work only with the special digital ignition coil"

I have Altair, and use two Lucas 6V coils.

When I purchased the Altair, there is NO MENTION of a requirement to use their dual post coil. In fact, the drop down option menu OFFERS 6V Lucas coils at point of sale.
Resistor plugs and caps.
Resistor plugs and caps.
 
concours said:
I am more confused than ever now.

"....this system isdesigned to work only with the special digital ignition coil"

I have Altair, and use two Lucas 6V coils.

When I purchased the Altair, there is NO MENTION of a requirement to use their dual post coil. In fact, the drop down option menu OFFERS 6V Lucas coils at point of sale.
Click to expand...


The quote is from the Smart-Fire instructions, however, both Smart-Fire and Altair are digital so need resistor plugs or caps (Pazon's underline in the quote).

Smart-Fire:
https://www.pazon.com/files/PDF/PDCTS1.pdf
"A 5K resistor plug cap as supplied with the system should be fitted to the h.t. lead. Alternatively, a resistor spark plug can be used. A resistor plug & resistor cap can be used together, although it is not necessary to use both."

Altair:
"5K resistor plug caps should be fitted to the h.t. leads. Alternatively, resistor spark plugs can be used. Resistor plugs & resistor caps can be used, although it is not necessary to use both."
 
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I have had an issue with NGK spark plug caps, on a dual plugged BM twin, 2 of the supposed NGK caps have no electrical continuity and (possibly) as a result one of the 2 coils burnt out. i understand that NGK have stopped making plug caps, so it is possible that the ones I fitted to the bike were fake CAPS BRANDED AS NGK.

Check what you are getting supplied, I will be fitting basic plug caps and resistor spark plugs.
 
chasbmw said:
I have had an issue with NGK spark plug caps, on a dual plugged BM twin, 2 of the supposed NGK caps have no electrical continuity and (possibly) as a result one of the 2 coils burnt out. i understand that NGK have stopped making plug caps, so it is possible that the ones I fitted to the bike were fake CAPS BRANDED AS NGK.

Check what you are getting supplied, I will be fitting basic plug caps and resistor spark plugs.
Click to expand...
Whilst it is certainly not a 100% guarantee, buying from a trusted retailer, rather than some faceless eBay schmuck, is definitely a way to reduce the chances of buying counterfeit crap.

It is why I only buy plugs etc from the Green Spark Plug Company.
 
chasbmw said:
2 of the supposed NGK caps have no electrical continuity and (possibly) as a result one of the 2 coils burnt out.
Click to expand...

Even genuine (are there fake NGK caps?) caps don't last forever.

chasbmw said:
i understand that NGK have stopped making plug caps,
Click to expand...

Still plenty about.

chasbmw said:
Check what you are getting supplied, I will be fitting basic plug caps and resistor spark plugs.
Click to expand...

There are certainly fake plugs.

www.ngkntk.com

Fake or not?

Beware of fake spark plugs: 5 step guide how to identify fake vs genuine by NGK spark plugs technical experts | Official NGK technical tipps
www.ngkntk.com www.ngkntk.com
 
Schwany said:
I have no first hand experience doing that with TriSpark ignition, but I would imagine misfiring would be a symptom of too much residence. If you ran resistor caps, resistor plugs and carbon core wire, it would definitely act poorly. EI is sensitive.
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As I understand it, the resistors are there to prevent / reduce any reflected voltage from damaging the electronics. Correct me if I am wrong.

That 5k or even 10k is nothing compared to the resistance provided by the spark plug gap.
 
stuck amals said:
As I understand it, the resistors are there to prevent / reduce any reflected voltage from damaging the electronics. Correct me if I am wrong.

That 5k or even 10k is nothing compared to the resistance provided by the spark plug gap.
Click to expand...

Not sure about what is right or wrong. Above my pay grade. All I know is if the plug wire, plug cap, and plug are all resistor type, it is not necessary nor as I understand it recommended for EI. That doesn't mean I have not gaslighted myself about what is the right thing to do with EI. What I'm doing works. Only parts in the electronic ignition path on my Norton engine that are resistor type are the plugs.
 
Schwany said:
Not sure about what is right or wrong. Above my pay grade. All I know is if the plug wire, plug cap, and plug are all resistor type, it is not necessary nor as I understand it recommended for EI. That doesn't mean I have not gaslighted myself about what is the right thing to do with EI. What I'm doing works. Only parts in the electronic ignition path on my Norton engine that are resistor type are the plugs.
Click to expand...
I have the Power Arc E/I that Old Britts sold and you must run resister plugs and plug wires or it may damage the unit and void warranty. Mine works well as designed.
 
Larry S said:
I have the Power Arc E/I that Old Britts sold and you must run resister plugs and plug wires or it may damage the unit and void warranty. Mine works well as designed.
Click to expand...

Fantastic!!

Excuse my being somewhat generic in my previous response. OP was asking about TriSpark which is what I use. Both the Boyer and TriSpark I have used worked fine with just resistor plugs.
 
stuck amals said:
As I understand it, the resistors are there to prevent / reduce any reflected voltage from damaging the electronics. Correct me if I am wrong.

That 5k or even 10k is nothing compared to the resistance provided by the spark plug gap.
Click to expand...
The resistors are there to reduce noise. Resistors know nothing of direction of current flow. In a spark plug application, they are a part of a inductance, capacitance, resistance circuit and the high-speed noise is filtered by the additional of a little resistance. That resistance is minor when compared to the resistance of the plug gap and more importantly, non-existent to the current flowing through it to the plug gap.

Noise in the air can trigger various things in a digital circuit but is unlikely to physically damage it. Back current in the coil is high enough to destroy unprotected electronics but the resistance of the secondary has nothing to do with that and the designers of the EIs know to protects against it. Resistor caps/wires/plugs do increase the voltage needed for a spark to jump the gap, but there is plenty of excess voltage available so that's a non-issue.
 

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