Spark plug wires, to resist or not to resist that is the que

I going to replace the plug wires but reuse my nice NGK caps. I've been told that I must use resister wire because I'm using electronic ignition. Is this true? Or can I use any good quality wire. Who sells lengths of resister wire?

gtsun said:

I going to replace the plug wires but reuse my nice NGK caps. I've been told that I must use resister wire because I'm using electronic ignition. Is this true? Or can I use any good quality wire. Who sells lengths of resister wire?

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Depends if your NGK caps are resistor type or not?

Makers of digital electronic ignition systems (or Sparx regulator/rectifiers) often specify that 5 kOhm resistance is required.

So you either need resistor plug caps, or resistor plugs or resistor wires. However as resistor spark wire has a certain amount of built-in resistance per unit of length, it is often easier to use resistor caps or plugs with copper spark wire which is supposed to more reliable than resistor wire.

Geez! Nothings ever simple. I'm not sure if my plug caps are resister or not. I will look. Are "resister" spark plugs available for a Commando? If I understand what you are saying, I just need something to be resister. Either the caps or the plugs?

gtsun said:

I going to replace the plug wires but reuse my nice NGK caps. I've been told that I must use resister wire because I'm using electronic ignition. Is this true? Or can I use any good quality wire. Who sells lengths of resister wire?

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The easiest route is to use resistor plugs if you already have some non-resistor caps you want to use. Then you can use solid copper leads. Resistor wire is tricky because the amount of resistance is a function of lead length. If you want to use resistor wire, any automotive store carries it. Solid copper wire is more difficult to find. I learned the hard way that is is not OK to combine resistor leads AND caps. Long story. NGK resistor plugs for the Commando are BPR7ES.

I learned the hard way that is is not OK to combine resistor leads AND caps. Long story

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Can you elaborate a bit? After converting to a Sparkx 3 phase, I toasted 2 batteries from overcharging before being told about the resister caps.

I've been dealing with a mid range misfire, poor metering, or who knows what for the better part of 3 years since I had some Amals put on to replace the mikuni. I and others have been through the Amals half a dozen time. I was about ready to go back to the mikuni, but decided to try new coils and wire as a Hail Mary. When I pulled the old wires off, I noticed that I'd installed resister wire along with the caps somewhere along the way. If a little is good, more is better, right?

I'm going to install the new coils tomorrow, but am curious if combining the resistor caps and wire could have been the cause of my mid range misery.

Ok. I checked my plug caps. They are NGK, LB05F ceramic resistor (5K) caps. So does this mean I can use regular non resistor wire and my non resistor NGK BP7ES plugs?

Yes. Your caps supply all the resistance needed. Don't add more.

There should be no correlation between using resistor wires/caps/plugs and you toasting 2 batteries. Really 2 different systems on your bike. If you toasted batteries then there is a problem with your regulator, not your ignition system.

lrutt said:

There should be no correlation between using resistor wires/caps/plugs and you toasting 2 batteries. Really 2 different systems on your bike. If you toasted batteries then there is a problem with your regulator, not your ignition system.

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Thyristor rectifier/regulator units are sensitive to RFI and can overcharge the battery if exposed to it. Hence the recommendation for resistor suppression devices.

I believe it also depends on wiring and layout. My Sparx regulator is well grounded and a long way from the ignition and I've never had any issues without resistor devices.

Vertigo said:

I learned the hard way that is is not OK to combine resistor leads AND caps. Long story

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Can you elaborate a bit? After converting to a Sparkx 3 phase, I toasted 2 batteries from overcharging before being told about the resister caps

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SPARX 3-phase definitely requires 5K ohms of resistance somewhere in the ignition circuit. I installed resistor wires AND resistor caps on my 61 Matchless G12 restoration. Not sure why, but it was probably because the NJK resistor caps were supplied with the Boyer Micropower ignition system and I had the suppressor wire in my shop. I never thought that MORE resistance could be a bad thing. The bike was fitted with a Boyer ignition, high-output SPARX alternator and voltage regulator. When I fired up the bike, the battery would not charge. It took me a long time to figure out what was going on but I eventually discovered that the extra resistance in the ignition circuits was interfering with the regulator. In my simplistic way of looking at it, the overly suppressed ignition was somehow fooling the regulator into putting out lower voltage. I have since confirmed this with several people who know a lot more about electronics than I do. When I swapped out the carbon fibre ignition leads for solid copper, the battery started charging just fine. So, I am certainly convinced that there CAN be a link between the ignition system and the charging circuit. I think it also depends to a large extent on the physical layout of your ignition components relative to the location of your voltage regulator as mentioned by maylar. The best way to deal with it is to install resistor plugs OR resistor wire OR resistor caps. I have heard some comments about the lack of reliability of resistor caps and it seems like resistor wire is going to vary as a function of lead length. So the best way to go may be to use resistor plugs. On my Dominator restoration (also with a Boyer ignition, high-output SPARX alternator and solid state voltage regulation), I wanted to use some vintage Champion caps so I chose to use resistor plugs (NJK BR7ES) with solid copper leads and non-resistor caps. I'll see how it goes!!

tpeever said:

Boyer Micro Power ignition system

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Hey Mr Peever- How does your bike start and run with that system? If that's the same one I had (with twin-output CDI type coil) it was a bit fussy.

Triton Thrasher said:

tpeever said:

Boyer Micro Power ignition system

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Hey Mr Peever- How does your bike start and run with that system? If that's the same one I had (with twin-output CDI type coil) it was a bit fussy.

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I had a bad controller box that Boyer replaced (first one I have ever had a problem with) and while I was waiting for them to replace it, I installed a standard Boyer black box with twin 6 volt PVL coils on the G12. That works fine although I suspect the timing may be wandering a bit due to timing chain tension. I think I know understand why the 18D2 distributors were quickly replaced by points on the end of the camshaft!! The Micropower setup is now on the Dommie and I haven't started it up yet. My biggest challenge with these Lucas 18D2 electronic conversions has been getting static timing set to get it running. No timing marks on the pickup plates, no marks on the alternator and no inspection holes in the primary cover. I am planning to leave the primary cover off the Dommie during startup so that I can strobe it without oil flying everywhere!! I'll let you know how I get on.

When you say yours was "fussy", what do you mean specifically?

On my Triton it seemed to need all connections in the 12V circuit to be better than perfect, or riding became a spluttering misery. The crimps supplied by Boyer were patently not good enough for their ignition. Various types of key switch only lasted months before the terminals inside became too loose or dirty for the ignition. Starting always involved big bangs and kickbacks.

Every connection in the HT circuit had to be dead tight or the RF from the sparking caused the ignition to shut down randomly. The paltry brass terminals supplied for the coil ends of the HT leads would not stay tight enough on the coil poles to avoid this problem. A little-known fact about NGK plugs is that the copper core becomes slightly loose in the threaded top terminal in use- not a problem unless you have Boyer Micro Power, waiting for an RF excuse to switch itself off!

It did idle more smoothly than the magneto though! Actually, it was almost the opposite of what I wanted electronic ignition for. I went back to a magneto.

I have Lucas RITA on a Guzzi and it works perfectly, even though the Italian wiring and switchgear looks ropier than the Triton's.

I can only offer that I converted to the 3-phase Sparx unit this last Spring. After reading the posts about voltage regulators not working without the appropriate resistance in the secondary ignition circuit I ordered the installation kit from Colorado Norton works. It comes with resistor plugs and resistor caps along with the appropriate plug wires and beefier wires for the regulator. After installation I tested the system and got a perfect charging voltage/current. I've had no problems with my charging system since and no noticeable decrease in performance. It starts first or second kick and runs like an Impala (not the Chevy kind).

On behalf us electronically challenged people I will ask the question, Why are not enough resistor bits, plugs, caps, wire etc. not too good, and equally why are having too many bits also not good?
On my Norton I have Tri-spark with NGK caps, I know it's not a Norton, but, on my BSA ,12v system, I have boyer ign system & power box, with champion caps,(the black ones with the logo on them), champion plugs, and standard copper wire HT leads is this ok?, if not why not?
Please don't mock the simpletons in this dept.
Thank you!
R

Resistance in a HT circuit is best kept low as the electrons like it that way, so with points or analogue boyer and boyer powerbox no resistance is required (but the neighbours TV will object). For digital ignitions and/or Sparx regulators you need some resistance to reduce the RF transmissions (the ones that cause the TV interference) so the electronics can get on with doing what they were designed to do. So on my Digitally ignitioned MK2A I had resistor spark plugs but all else is non resistance, interference is nil so it is staying that way. High resistance HT is best avoided, its a carbon wire that fractures easily leaving you with no spark.

I shy away from resistor caps and wire. I've had a cap go full resistance and cook an Acell coil. Resistance wire may not really be a problem but it's always seemed fragile to me. Resistor plugs on the other hand are widely available anymore. And one does swap them out with some regularity if they do have some kind of longevity problem.

Regarding the Boyer MicroPower. I installed one recently that I got a long time ago. Runs great. But I have a question. I got the coil for it from Nology. It's the small dual lead unit for CDI. But it turns out there are several units that they put out in that configuration. One is 0.6 Ohm and the other is 3.0 Ohm, (2.4 Ohm actual.) Could someone with the MicroPower unit check the resistance across the pos and neg feeds so I can see if I got the wrong one. It seems to work just fine, but..

P.S. I mean the resistance across the inputs on the coil.

As far as needing reliable power to the ignition, nothing says, "relay" louder. It doesn't take more than running the power feed that normally connects to the Boyer to connecting it to power up a relay switch. The relay has a fused line directly from the battery and feeds the ignition. No ignition switch, kill button, or fragile bullet connections. The amount of current the relay consumes to maintain the connection is next to nothing and the sealed box, approx. 1"x1" keeps the contacts clean.
http://www.tonyfoale.com/Articles/Ignition/Sidebar.htm

bpatton said:

I got the coil for it from Nology. It's the small dual lead unit for CDI. But it turns out there are several units that they put out in that configuration. One is 0.6 Ohm and the other is 3.0 Ohm, (2.4 Ohm actual.) Could someone with the MicroPower unit check the resistance across the pos and neg feeds so I can see if I got the wrong one. It seems to work just fine, but..

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For Micro Power, you need the 0.6 ohm coil. The 3 ohm is not a CDI coil.