Milwaukee Eight (M8) 2017 and up M8 Air and Liquid Cooled discussion
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Old Apr 9, 2026 | 06:53 PM
  #31  
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John Harper
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Plugs look decent, but definitely time to change them.

John
 
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Old Apr 10, 2026 | 10:19 PM
  #32  
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Originally Posted by John Harper
Plugs look decent, but definitely time to change them.

John
That was at 30K. I'm at almost 60K miles. I'll do the next set at 80k, 20k miles just to start to watch for excessive wear.

 
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Old May 22, 2026 | 11:24 AM
  #33  
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Default Spark plugs

Just got a deal on another bike a 2017 RK after changing fluids I decided to change plugs and wires. Only 13,000 miles and after pulling the outward plugs I was surprised to see NGK iridium plugs BUT after pulling the tank there was the original Harley plugs. Funny part is I bought the bike from a friend who’s owned Harley’s for at least 30 years! You buy used you just never know?

 
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