NGK BM6F Spark Plug – Stock No. 6221
The NGK BM6F is a standard nickel spark plug for small engines. It offers reliable cold starts, clean idle, and steady performance. The copper core draws heat away from the tip to reduce fouling, especially useful in two-stroke use. The solid terminal suits fixed plug caps often found on garden machinery and small motorcycles.
Use it to refresh tired ignition, improve starting, and keep combustion consistent. It is a non-resistor plug, so only use where a non-resistor type is specified.
- Reliable starting and smooth running in small-capacity engines
- Durable nickel electrode with copper core for stable heat control
| Part number | BM6F |
|---|---|
| NGK stock number | 6221 |
| Part category | 686 – Spark Plug |
| GTIN | 087295162217 |
| Thread diameter | 14 mm |
| Thread reach | 9.5 mm |
| Hex size | 20.8 mm (13/16 in) |
| Seat type | Gasket |
| Heat range | 6 (NGK scale) |
| Resistor | No |
| Terminal type | Solid terminal |
| Electrode material | Nickel alloy, copper core |
| Electrode design | Standard, non-projected |
| Factory gap | 0.7 mm (adjust to manufacturer spec) |
Fitment guidance
Commonly used in many small engines, including two-stroke garden tools, scooters, mopeds, small off-road bikes, and marine outboards that specify a 14 mm, short-reach, non-resistor plug with a solid terminal. Please use the vehicle lookup to confirm fitment or check the Vehicle Fitment tab for full details.
Note: Only use a non-resistor plug if specified by the manufacturer. If your ignition requires an R-type plug, choose the correct resistor equivalent.
The price displayed is for a single plug, please add the desired amount to your basket.


