Racing plug 4857

【NGK R7420-105 Racing Plug 4857 ngk r7420-105-4857】
Racing plugs, recommended for two-wheelers and four-wheelers, come in various types designed to further improve performance when used with engines that have increased output due to racing, circuit driving, or tuning.
Consequently, their shape differs from the manufacturer's standard plugs, and the plug's lifespan and low-speed performance may be slightly compromised.
However, on the other hand, they are developed and designed to fully exhibit performance even in extremely highly tuned engines or under very severe operating conditions, with a wide range of heat ratings available.
Please select the appropriate type for your specific engine to achieve full performance.
Points to consider when choosing racing plugs:
From the part number of your genuine plug or the plug currently in use, determine the screw size, plug type, and shape, then select the corresponding type.
Please refer to the manufacturer's website for guidance on how to choose the ignition end shape.
The heat rating needs to be selected to maintain the plug's ignition end at the optimal temperature range, taking into account the increased combustion temperature due to engine output improvement and operating conditions.
Simply increasing the heat rating alone will not improve engine performance.
Generally, for street use, ratings of 7 to 8 are used; for track day specifications, 8 to 9; and for racing specifications, 9 to 10.
The presence or absence of a resistor in the plug makes almost no difference nowadays due to improvements in ignition system performance.
Resistor types will become mainstream in the future.
Conversely, non-resistor types may cause engine problems in some models of some vehicle types.
In such cases, always use a resistor type.
*The image is for illustration purposes only, and the design and specifications of the products shown are subject to change without prior notice. Thank you for your understanding.