NGK D6HA Spark Plug – Stock No. 6512
The NGK D6HA is a standard nickel spark plug for small-capacity engines. It offers reliable ignition, consistent performance, and strong durability for everyday riding.
It uses a 12 mm thread with a gasket seat and a short 12.7 mm reach. The heat range is 6, which suits many air-cooled and smaller four-stroke engines. It is a non-resistor type for a strong spark signal.
Use this plug as a like-for-like replacement where D6HA is specified, or where the size, reach, and heat range match the original plug.
- Stable cold starts and smooth idle
- Good service life with copper core heat dissipation
- Non-resistor design for a clean, strong spark
Broad compatibility
Common in many small motorcycles, scooters, and ATVs that use a 12 mm gasket-seat plug with 12.7 mm reach and NGK heat range 6. Always confirm with the vehicle lookup or check the Vehicle Fitment tab.
| Part number | NGK D6HA |
|---|---|
| NGK stock number | 6512 |
| Part category | 686 – Spark Plug |
| GTIN | 087295165126 |
| Thread size | M12 x 1.25 |
| Reach (thread length) | 12.7 mm (1/2 in) |
| Hex size | 18 mm |
| Seat type | Flat seat with gasket |
| Heat range | 6 (NGK scale) |
| Resistor | No |
| Terminal | Solid terminal |
| Centre electrode | Nickel alloy with copper core |
| Ground electrode | Standard J-type |
| Projected tip | No |
| Factory gap | 0.7 mm (check and adjust to spec) |
Tip: Always check the required heat range, thread, reach, and gap for your engine before installation.
The price displayed is for a single plug, please add the desired amount to your basket.


