X1/9 Spark Plug - NGK V-Groove - Set of 4

NGK recommended spark plug for both 1300 and 1500 models. Use with 0.7mm gap for original specification ignition systems. This is a resistor type plug to lower radio frequency interference. Sold as a set of 4.

These plugs have a 90º groove cut in the centre electrode that forces the spark to occur at the periphery of the electrode resulting in

• Less material to obstruct burn - faster flame kernel growth;
• Less heat energy absorbed by electrode mass – reduced quenching effect;
• Enhances the potential gradient - less voltage required to create spark;
• No loss of service life;