NGK 7901 Spark Plug

Laser Iridium Spark Plug Overview

NGK 7901 is a Laser Iridium spark plug built for specific Honda ATV applications. It combines an iridium center electrode tip with a nickel ground electrode and a standard ground design for consistent ignition performance.

Key Features

• Laser Iridium construction for stable spark delivery
• Copper core center electrode for efficient heat transfer
• Standard ground electrode design with a single ground electrode
• Pre-gapped to 0.036 inches per OE manufacturer specification
• Flat seat, 12 mm thread diameter, and 18 mm hex size
• 5000 ohm resistance and stud terminal type

Detailed Description

This NGK spark plug is engineered to match the original equipment style used in Honda TRX500FA FourTrax Foreman Rubicon, Honda TRX500FPA FourTrax Foreman Rubicon with EPS, Honda TRX500FPA FourTrax Foreman 4x4 AT w/ Power Steering, and Honda TRX500FGA FourTrax Foreman Rubicon GPScape applications. The IJR7A9 design, sold under part number 7901, uses an iridium center electrode tip and a copper core to support reliable ignition and heat control in demanding powersports use. This part cross-references Monroe Shocks & Struts (e.g., 5614) for the same application.

What It Is Used For

• Restoring weak or inconsistent spark
• Replacing worn electrodes and degraded firing surfaces
• Addressing hard starting caused by plug wear
• Maintaining proper ignition performance under load
• Supporting service replacement on Honda TRX500FA and TRX500FPA models

Installation Notes and Tips

Verify the application by year, model, and engine configuration before installation. The plug is specified with a 0.036-inch gap according to OE manufacturer guidance, so confirm the gap during service and adjust only if required by the application. Use the correct 18 mm spark plug socket and tighten to the vehicle manufacturer’s torque specification.

Quality Assurance

NGK is a major OE supplier of spark plugs in North America and has more than 80 years of automotive experience. The brand manufactures to original equipment standards and supports a wide range of automotive and powersports applications.