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M8 Spark Plug Equivalents?

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Old Sep 27, 2017 | 01:55 PM
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Default M8 Spark Plug Equivalents?
I've been able to find lots of information providing equivalent spark plugs in various brands for the HD-6R12 spark plug, but virtually no equivalency tables for the HD-6R10 plug that's stock in the M8 engine. Does anyone know the equivalent plug in a NGK, Champion, etc.?
 
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Old Sep 27, 2017 | 02:39 PM
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Originally Posted by rwt
I've been able to find lots of information providing equivalent spark plugs in various brands for the HD-6R12 spark plug, but virtually no equivalency tables for the HD-6R10 plug that's stock in the M8 engine. Does anyone know the equivalent plug in a NGK, Champion, etc.?
NGK is 6R10 that's who makes them for HD
 
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Old Sep 27, 2017 | 03:10 PM
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Originally Posted by rwt
but virtually no equivalency tables for the HD-6R10 plug that's stock in the M8 engine. Does anyone know the equivalent plug in a NGK, Champion, etc.?
Champion RG6HCC is in the M8's
 
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Old Sep 27, 2017 | 04:44 PM
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You need new ones already?
 
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Old Sep 27, 2017 | 05:50 PM
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I've never had to change a spark plug on a modern 4 stroke....
 
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Old Sep 27, 2017 | 06:53 PM
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Good question and thanks for asking. Have had it for years for the TC but having recently picked up an M8 this will be saved.
 
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Old Feb 1, 2019 | 04:36 PM
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NGK Iridium is CR9EIX I believe.
 
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Old Feb 2, 2019 | 02:42 AM
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What's wrong with Harley plugs? No magic in aftermarket plugs.
 
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I second that.
 
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Old Feb 2, 2019 | 11:07 AM
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FYI have 2 sets (4 plugs) screamin eagle performance plugs P/N 31600085 for sale $35 shipped conus.
 
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