Dual plugging: 14, 12 or 10mm?

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mattcfish
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Joined: Mon Aug 02, 2010 11:18 pm

Re: Dual plugging: 14, 12 or 10mm?

Post by mattcfish »

Garnet wrote:
mattcfish wrote:Are we slipping into the dreaded resister vs non-resister plug discussion?

God no! I think that is overblown, just ramblin on.
I can't resist :D saying this. Before I joined this group, I ran my /6 on resister plugs for 16 years. I've always had electronic ignitions. It didn't seem to cause any issues. Maybe it's more of a problem with points?
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
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Garnet
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Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: Dual plugging: 14, 12 or 10mm?

Post by Garnet »

I have run both in most all of my airheads and not noticed any differance on the butt dyno chart.

On a dual plug setup I would imagine it would be best to run both plugs the same, that is both resistor or both non-resistor.
Garnet

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Major Softie
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Re: Dual plugging: 14, 12 or 10mm?

Post by Major Softie »

AND, these bikes were originally setup to run with non-resistor plugs and resistor caps. You could run resistor plugs and non-resistor caps and have the same results.
MS - out
Garnet
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Re: Dual plugging: 14, 12 or 10mm?

Post by Garnet »

Major Softie wrote:AND, these bikes were originally setup to run with non-resistor plugs and resistor caps. You could run resistor plugs and non-resistor caps and have the same results.
On a stock bike most likely yes.

That starts to get tricky if you are useing an aftermarket electronic ignition.

Boyer for example specifies a 5K ohm resistor cap for use with thier Micro Digital units. Resistor plugs have only a few hundred ohm resistance (I think), which may not be enough to not damage the control unit.
Garnet

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Major Softie
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Re: Dual plugging: 14, 12 or 10mm?

Post by Major Softie »

Garnet wrote:
Major Softie wrote:AND, these bikes were originally setup to run with non-resistor plugs and resistor caps. You could run resistor plugs and non-resistor caps and have the same results.
On a stock bike most likely yes.

That starts to get tricky if you are useing an aftermarket electronic ignition.

Boyer for example specifies a 5K ohm resistor cap for use with thier Micro Digital units. Resistor plugs have only a few hundred ohm resistance (I think), which may not be enough to not damage the control unit.
Yes, it was supposed to be implied that matching the resistance can be important for some systems, but I did not know that resistor plugs are that much lower than the 5k caps.
MS - out
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