Picture of AJP PR3-Supermoto 125 15 Main Bearing Right Hand Side

Part Description

AJP PR3-Supermoto 125 15 Main Bearing Right Hand Side

28x68x18mm KOYO

Delivery and Returns

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Motorcycle Spark Plugs
Wemoto Spark Plug Guide

Spark Plug Basics

The spark plug has two primary functions:

  • 1 - Ignite air/fuel mixture
  • 2 - Transfer heat from the combustion chamber

Spark plugs carry electrical energy and turn fuel into working energy. A sufficient amount of voltage must be supplied by the ignition system to spark across the spark plug's gap. This is called "Electrical Performance." The temperature of the spark plug's firing end must be kept low enough to prevent pre-ignition, but high enough to prevent fouling. This is called "Thermal Performance", and is determined by the heat range selected.It's important to remember spark plugs do not create heat, they only remove heat. The spark plug works as a heat exchanger by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine's cooling system. The heat range is defined as a plug's ability to dissipate heat.

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