4 X NGK Copper Core Motorcycle / Bike / Motorbike Spark Plugs - CR9E

Standard Copper Core plugs - NGK uses Copper wire in place of the iron core found in conventional plugs and is the secret to their wide heat range. The Copper core electrode provides superior heat conductivity, allowing quicker dissipation of heat and helping in the cooling of the electrode tip and insulator tip; thus preventing hot spots that could cause pre-ignition.

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