3 ohm spark plug caps?

[Manfred]

I know my 1987 R80RT uses 5 ohm spark plug caps with no-resister plugs. I've ordered an ACCEL 140403S Universal Super Coil Kit and it comes with 3 ohm caps. I don't yet know what the diameter of the wires are with this kit. If I use the cables and caps that come with the kit, should I use resister plugs or stay with no-resister plugs?

[guy]

Get a few feet of wire copper or steel and NGK sparkplug boots with the right resistance
built in, assemble with good electrical grease on both ends to seal out moisture.
Guy

[Manfred]

I have 2 year old NGK wires and caps on the bike right now. If they are the same diameter - or close enough - I can use them.

[Kurt in S.A.]

5K? 3K? If the caps are indeed 3K ohms, I think I'd use non-resistor plugs. 3 ohm caps...and you need resistance somewhere.

Kurt in S.A.

[Manfred]

The coil kit showed up today. The plug wires with it are fat - 9mm I think. I was able to connect my "stock" (6 mm) cables to the coil, keeping the 5 ohm caps. She stated up really nice. I will keep an eye on the wires.

What is the opinion of 0 ohm caps and resister plugs?

If I end up going with the fat wires, I will revisit this.

[Kurt in S.A.]

A couple of reasons that I've read: 1) you might forget later and put non-resistor plugs with non-resistor caps...probably not good for the electronic ignition in a variety of ways. Going the other way, resistor cap with resistor plugs is not horrible, but it might make a marginal system more marginal. 2) according to the 'bum, resistor plugs are "backdoor" resistors or inductors and might still create problems for the electronic ignition.

Kurt in S.A.

[Manfred]

I read that on Snowbum's site. If I were to use 0 ohm caps, they would require the spin-on top that my 5 ohm caps do not. This would be a physical reminder of something different, beyond the notes I would make in my maintenance file.

I wonder, in this day and age, how often brand name plugs (Bosch?) have resisters fail.

[Duane Ausherman]

As I read this thread I wonder just what is going on. I never heard of a 3, or 5 ohm cap. I think that you must mean 3k ohms = 3000 Ohms. A 3 ohm cap is the same as zero ohms.

If the eletronic ignition cares about a few k ohm more or less I would be very surprised.

The only (repeat ONLY) reason for any resistance anyplace in the secondary of the ignition system is for reducing radio noise. It is to comply with the law. Do you really care if your ignition system makes some noise that an AM radio in the car next to you? I didn't think so.

I would go with real copper wire and zero resistance spark plug caps.

[Manfred]

You're right, Duane. It's 5k and 3k ohms - I dropped circuit analysis in college. Snowbum says running without resistance will fry the bike's electronics. That's something I don't know anything about.

The Accel kit came with silicone wire. I understand the reason copper is better for conducting electricity.

Do you think my 6mm wires are OK for a coil kit that came with 9mm wires? I will contact the mfr and check with them as well.

[Garnet]

I'd check into that fat wire. Usually an 8.5 or 8.8mm wire is what is called "spiral wound" resistor wire. It is very fine stainless wire wound around a kevlar core and covered with a heavy silicone jacket. It has a resistance of about 100 ohms per foot and is used as an upgrade from carbon wires in automotive aftermarket.

I'd try and see if you can fit standard 7mm solid core wire as it gas 0 resistance.