Two NGK Spark Plugs for Harley-Davidson Shovelhead and Evolution side by side, one white with blue text and one silver with the word “IRIDIUM” printed on the ceramic insulator.

NGK Spark Plug for Harley-Davidson Shovelhead and Evolution

$5.95

SKU: 108-0260

Low stock - 2 items left
Inventory on the way

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NGK Spark Plug for Harley-Davidson for Harley-Davidson Shovelhead and Big Twin Evolution

NGK plugs are right at home in a Harley-Davidson—for the money, many riders feel there's no better brand for a bar-and-shield bike.

Choice of construction
- Copper-core plugs offer great conductivity and strong spark and their price makes them an economical choice for riders who prefer spending the time to make more frequent swaps in order to combat the detrimental effects on the gap due to normal erosion
  - Direct replacement for the OEM plug in engines specified in the fitment section with the recommended heat range for listed applications
  - Conventional copper core plugs yield strong, consistent spark
- Iridium plugs feature fine-wire iridium that some riders feel improve idle and acceleration, especially in motorcycles that have been tuned aggressively
  - They usually have a longer service life if the motorcycle's air-fuel ratio is correct at all throttle angles
Resistor suppresses electromagnetic interference so the ECM and other onboard electronics function correctly
Trivalent metal plating on plug body
- Resists corrosion and seizing in aluminum cylinder heads
Corrugated insulator ribs help prevent flashover (when the spark moves along the outside the plug rather than inside it)
Sold individually
- Late Shovels and Evos have single-plug cylinder heads—order a quantity of two for a complete tune-up