Autolite 4054 Spark Plug

Autolite 4054 Copper Spark Plug

Autolite 4054 is a copper non-resistor spark plug built for quick starts, smooth acceleration, and improved fuel economy. It uses OE-style form, fit, and function, making it a direct replacement choice for a wide range of motorcycles, snowmobiles, and powersports applications.

Key Features

• Copper center electrode for reliable ignition performance
• Non-resistor design for applications that call for a resistor-free plug
• Tapered ground electrode tip for consistent spark exposure
• Flat seat, 14 mm thread diameter, and 0.750 in. reach
• Pre-gapped to 0.030 in. / 0.80 mm for many listed applications
• Removable nut terminal for flexible connection styles

Detailed Description

The Autolite 4054 spark plug is engineered with a copper center electrode, nickel ground electrode, and ceramic insulator to support dependable combustion in older and performance-oriented engines. Its standard regular electrode design and flat seat match the dimensions called for in many fitments, including KTM 250 XC, KTM 300 XC-W, and Honda FL400R Pilot applications. This part number 4054 is also listed for a broad range of Kawasaki, Suzuki, Yamaha, Polaris, and Ski-Doo models where the specified gap and thread dimensions align.

Autolite positions the Copper Non-Resistor Spark Plug line as an OE-style replacement option for foreign and domestic vehicles, and this plug follows that approach with a conventional copper-core construction. Part number 4054 is cross-referenced to Champion Spark Plug 821 and Standard Ignition 7701 for the same application.

What It Helps Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from weak or inconsistent spark delivery
• Loss of throttle response during acceleration
• Reduced combustion efficiency from incorrect plug gap or worn electrodes
• Misfire concerns in engines specified for a non-resistor copper plug

Installation Notes and Tips

Verify thread diameter, reach, seat type, and gap before installation. The listed fitments include multiple gap specifications, so confirm the engine’s required setting against the vehicle service information before use. Install to the manufacturer’s torque specification and inspect the plug wire or cap connection when replacing the spark plug. Fits 2012-2018 KTM 250 XC, 2006-2018 KTM 250 XC-W, 2012-2018 KTM 300 XC, 2014-2018 KTM 300 XC-W, 2011-2013 Husaberg TE250, 2011-2013 Husaberg TE300, 2001-2004 Suzuki JR80, and other listed applications exactly as cataloged. Fits 1981-1986 Honda ATC250R, 1977-1984 Honda FL250 Odyssey, and 1989-1990 Honda FL400R Pilot where the specified plug dimensions match.

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and original equipment manufacturers, and this spark plug is built to OE form, fit, and function standards for the listed applications.