The NGK BPMR7A (Stock #4626) is the high-performance resistor-type spark plug equivalent to the Bosch WSR6F. As a critical replacement for STIHL part numbers 0000 400 7000 and 1110 400 7005, this plug is designed for the rugged 2-stroke engines found in professional chainsaws, cutoff saws, and trimmers. It provides the reliable ignition and heat dissipation needed for intense outdoor work.
Featuring a 98% pure copper core, the BPMR7A ensures superior heat removal to prevent engine overheating and pre-ignition. The trivalent metal plating offers advanced anti-corrosion and anti-seizing properties, while the corrugated ribs prevent electrical flashover for a consistent spark. Pre-gapped at 0.020" (0.5mm), it meets the exact factory specifications for the most popular STIHL handheld equipment.
Note: The NGK BPMR7A is the industry-standard resistor plug used to replace the Bosch WSR6F and Champion RCJ6Y, ensuring your equipment's ignition system remains interference-free.
Key Features & Benefits
Professional-Grade Ignition
- Resistor Construction: Specifically engineered to reduce electromagnetic interference, protecting your tool's ignition module and surrounding electronics.
- Trivalent Metal Plating: Eliminates the need for anti-seize during installation and protects threads from corrosion in wet or humid conditions.
- Triple Gasket Seal: Ensures a gastight seal to maintain full cylinder compression for maximum power output.
Superior Durability
- High-Alumina Ceramic: Provides exceptional insulation and mechanical strength, even under the extreme vibrations of a chainsaw or cutoff saw.
- Copper Core: Conducts heat away from the firing tip faster than standard nickel-core plugs, extending the life of the electrode.
- Broad Heat Range: Designed to prevent fouling at idle while resisting overheating at wide-open throttle.
Extensive STIHL Compatibility
- Chainsaws: Fits legendary models including the 026, 029 Farm Boss, 036, 044, 066, and modern MS series (MS 170, MS 180, MS 250, MS 260, MS 290, MS 361, MS 660).
- Cut-Off Saws: The standard plug for the TS 400, TS 410, TS 420, TS 700, and TS 800 series.
- Trimmers & Blowers: Compatible with FS 55, FS 80, FS 85, FS 120, and BG 55, BG 85, BR 420, BR 600 models.
Technical Specifications
| Brand / Model | NGK BPMR7A (Replaces Bosch WSR6F) |
| Thread Diameter | 14 mm |
| Thread Reach | 9.5 mm (3/8") |
| Hex Size | 3/4" (19 mm) |
| Standard Gap | 0.020" (0.5 mm) |
| STIHL Part # Cross-Ref | 0000 400 7000 / 1110 400 7005 |