Resistor plugs and caps.

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Pretty sure I got my answer from other threads but I figured I would make sure.
I should NOT be running with both resistor plugs and caps with a tri spark ignition correct?
As well, could the symptoms of doing so be a misfire on acceleration?
 
Pretty sure I got my answer from other threads but I figured I would make sure.
I should NOT be running with both resistor plugs and caps with a tri spark ignition correct?
As well, could the symptoms of doing so be a misfire on acceleration?
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.
 
I seem to recall posts about a misfire with Tri Spark being caused by certain reg / rectifier units creating electrical noise ?

Maybe a search will yield more info…
 
Yep, if are running a podtronics or similar aftermarket rectifier it will cause a misfire at low to intermediate rpms. Solution is to fit a mosfet type which filters the noise. Tri-Spark sells one and there are others available. Rectifier plugs or caps, not both.
 
As I understand it, the advice to run only 5k Ohm resistance (either plug or caps not both) derives from the less powerful older style capacitors and not the EI per se. My modern bonneville runs 10k Ohms resistance with both resistor plugs and caps together, using stock EI with a modern dual output capacitor. Similar setup on my classic mini running EI and 10k ohms per cylinder.

Also recall hearing Mr Marsh state he's run 10k Ohms on our bikes with the different EI's without noticeable issues.
 
I had the first version of the Trispark black box for triples on my T160 when I bought it, and the engine randomly cut out dead, sometimes after a mile and sometimes after 10 miles. It was random. All I had to do was turn the ignition off and then on and it would immediately restart, and off I went again until the next time it cut out. The first boxes became known to be susceptible to electrical noise and I also had a Podtronics rectifier fitted.
I spoke to Steve Kelly online and he said try it with resistor plugs and caps. I did this and it cured the problem. It never happened again, except when my confidence grew and I went back to cap only resistance, which immediately started the cutting out again.
I know now about mosfet rectifiers and in line resistors that are available to cure the problem.
But the reason that I am writing this is, I ran with resistor plugs, resistor caps and copper HT leads and didn't have a mis-fire with this set up at all. (Or any cut-outs).
 
I had the first version of the Trispark black box for triples on my T160 when I bought it, and the engine randomly cut out dead, sometimes after a mile and sometimes after 10 miles. It was random. All I had to do was turn the ignition off and then on and it would immediately restart, and off I went again until the next time it cut out. The first boxes became known to be susceptible to electrical noise and I also had a Podtronics rectifier fitted.
I spoke to Steve Kelly online and he said try it with resistor plugs and caps. I did this and it cured the problem. It never happened again, except when my confidence grew and I went back to cap only resistance, which immediately started the cutting out again.
I know now about mosfet rectifiers and in line resistors that are available to cure the problem.
But the reason that I am writing this is, I ran with resistor plugs, resistor caps and copper HT leads and didn't have a mis-fire with this set up at all. (Or any cut-outs).
Thanks, nice to hear 'Real' life experience.
 
I have a newer version (not the newest) TriSpark ignition and TriSpark MOSFET reg/rec. Never had a problem with it. Stainless steel core plug wire, MSD plug boots, and Autolite resistor plugs. As real as it gets. lol
 
I once fitted resister plugs and caps to my commando
It's fitted with Lucas Rita
It made it harder to start but apart from that made no difference to the running
 
Tri-Spark is now and always has been specified to use resistor caps OR wires. I do that but when I've experimented with neither there were no issues.

Tri-Spark Tri-0002 (Triples), Tri-0005a (Clockwise), and Tri-0005b (Counter Clockwise) when used will OLD PODtronics has no problem but soon after PODtronics was sold (don't remember when) and more where made, they started causing missing problems and Tri-Spark released an in-line noise filter (choke) that resolved the problem. Still later the PODtronics being produced made so much noise that the filter did not resolved it.

Today, the Tri-0006 is used for twins that are clockwise or counterclockwise. I quit using PODtronics long ago and switched them all the Tri-Spark VR-0030 (MOSFET). There no noise issues with any Tri-Spark ignition and VR-0030. I don't know if the Tri-0006 is affected by the PODtronics induced noise.

I did test a Tri-0005b with both resistor wire and caps at one point - it was actually an accident - everything worked fine.

CAVEAT: Many use NKG plugs. NKG does not produce plugs with the correct gap for standard Lucas coils. Norton specifies a plug gap of .023" to .028" (manual 065146). Triumph specifies .025" (manual 99-0947) and BSA specified .020" to .025" (manual 00-4175). Triumph and BSA used 12-volt coils and Norton 6-volt coils. I have no idea whether the 6- or 12-volt coils produce a higher voltage spark, but I set my plug gaps to .025". If you simply install NKG BPR6ES, BPR7ES, BPR8ES, BP6ES, BP7ES, BP8ES without setting the gap, your gap is too wide and resistance may cause a problem whether resistance wire, cap or both. A BPR6ES (Stock Number 7131) is factory set to .035" - way too wide. The BPR7ES (Stock Number 5534) and the BPR8ES (Stock Number 3923) are factory set to .031" (All per NKG - I haven't checked but I know they are all too wide).

Resistor plugs and caps.


AFAIK, all Champion standard and resistor plugs appropriate for a Commando come factory set at .025" gap.
 
I use NGK 5K ohm resistor caps, NGK BP7ES non resistor plugs and copper core non resistive wire with my updated Lucas RITA ignition. Works great.
 
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Just for information NGK announced late last year they have now stopped supplying / manufacturing plug caps , so i guess the NGK caps will soon dry up
 
Wow! Lot's of great info. Thanks everyone. Looks like I've got lots to check out and experiment with.
 
I use an inexpensive dual coil and it works well with the TriSpark. Also takes up less space than the stock oil filled tube coils. I think a strong battery is a plus.
 
Those with interference problems from regulators, has anyone tried fitting a big capacitor like the original Norton one?
 
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