NGK BPMR6ES Spark Plug – #4008 / 6775

The NGK BPMR6ES is one of the most trusted and widely used spark plugs in the outdoor power equipment world, especially for Honda’s legendary V-Twin GX-series engines (GX610, GX620, GX670 – 18, 20, and 24 HP). With its solid terminal, resistor design, and special “Projected Square” electrode configuration, this plug delivers outstanding ignitability, smoother idle, faster throttle response, and proven long life in both commercial and residential applications.

NGK’s BPMR6ES features a 5 kΩ ceramic resistor that dramatically reduces electromagnetic interference (RFI) that can affect modern electronic ignition modules and nearby radios or GPS units. The projected insulator nose and copper-cored center electrode provide superior heat dissipation, preventing both cold fouling in low-load situations and dangerous pre-ignition under heavy commercial use. The triple-gasket sealing process eliminates combustion gas leakage, while the pure alumina silicate ceramic insulator gives the plug higher dielectric strength and better thermal conductivity.

Key Features & Benefits

• Resistor type (5 kΩ) – eliminates radio noise and protects sensitive electronics
• Projected square platinum alloy electrode – excellent flame kernel growth and maximum ignitability
• Copper core center electrode – superior heat removal, prevents overheating
• Triple gasket seal – prevents combustion gas leakage
• Cold-rolled threads – prevents cross-threading and damage to aluminum heads
• Thread: 14 mm | Reach: 19 mm (3/4") | Hex: 13/16" (21 mm)
• Heat Range: 6 (medium-hot) – perfect balance for GX V-Twin engines

Direct OEM Replacement For

• Honda 98079-56145, 98079-56846 (most common)
• Yamaha 94702-00234-00
• Many Kohler Command Pro, Kawasaki FH/FR/FS series, and Briggs & Stratton Vanguard V-Twins

Common Equipment Applications

This plug is the factory-spec spark plug for virtually every Honda GX610, GX620, and GX670 engine found in:

• Zero-turn mowers (Scag, Exmark, Ferris, Bad Boy, Toro, Hustler, etc.)
• Riding tractors & garden tractors
• Commercial walk-behind mowers
• Pressure washers & generators
• Concrete saws & construction equipment

Service Life & Recommendations

Under normal commercial use (mowing, landscaping, construction), NGK recommends replacement every 100–150 hours or annually. In severe dust conditions (dry cutting, heavy field mowing), inspect every 50–75 hours. A fresh set of BPMR6ES plugs will restore lost power, improve fuel economy by 3–8 %, and eliminate hard hot-restarts that are common with old, fouled, or incorrect plugs.

Cross Reference Chart

When you need the absolute best plug for your Honda V-Twin powered equipment, accept no substitutes. Stock up on the NGK BPMR6ES and keep your fleet running strong all season. In stock and ready to ship today from HL SUPPLY!