The Bullet Board

I'm going to change my stock metal plug cap for an NGK cap. I'm running a Nippon Denso iridium plug. I have NGKs in both 5k resistance and zero. Will the zero resistance be ok?

If it's a resistor plug (which I think all Iridium plugs are...) you can use a zero resistance cap.

Aha! I checked the description online. Each one says it's a 'resistor' plug.
Zero caps it is!

Guaire wrote: ↑Sat Jul 11, 2020 4:51 pm I have NGKs in both 5k resistance and zero.

Bill, any one with a drawer full of caps should have one of these
https://westerncyclesupply.com/flashing-spark-plug-cap/

I bet it looks great at night, flashing like mad! Actually, anything that creates visual noise on a bike is a good thing!
BTW - what’s the resistance on that thing? Would it stand up to a big fat Dyna Coil?

A copper HT wire has no suppression resistance.
A carbon particle HT wire has 5k suppression resistance.
Some plug caps have 5k suppression resistance and some don't.
Some spark plus have 5k suppression resistance and some don't.

The rule is to have only one 5k suppression resistor in the HT circuit. If you have one in the plug, or the cap, or the wire, that's all you want. Don't stack up multiple 5k resistors because it will just cut down the spark, and do no additional good for rf suppression.
Use only one resistor in the line.