# R0409B-8 NGK Racing Spark Plug | Genuine NGK Spark Plug

## 🔧 Product Description

**NGK Racing Spark Plug – Part Number: R0409B-8**

NGK racing spark plugs are built for sustained high-RPM, high-temperature competition use, with precious-metal electrodes and cold heat ranges chosen for heavily loaded engines. Racing plugs are application-specific – heat range selection is critical, so confirm the specification for your engine before fitting.

## ⚙️ Key Features

-   Competition-grade construction for sustained high RPM and cylinder temperatures
-   Cold heat range for heavily loaded engines
-   Pure alumina silicate ceramic insulator, providing superior strength and better heat transfer
-   Triple seals prevent leakage

## 📏 Specifications

-   NGK stock number: 7791
-   Thread: 10 mm
-   Reach: 19 mm (3/4 in)
-   Hex: 16 mm (5/8 in)
-   Seat: Gasket
-   Terminal: Threaded stud
-   Type: Fine Wire Resistor, Partial Thread

## 🚘 Application

Listed in NGK's application charts for marine, motorcycle, ATV and snowmobile equipment. The chart shows a 0.5 mm gap for these engines, but check it against your engine's manual before fitting.

-   Honda CRF250R (250, 2009-2005) – Motorcycle

## 📦 Condition

-   Brand new genuine product
-   Supplied in original packaging

## Details

- **Price:** 104.0 AUD
- **Vendor:** NGK
- **Type:** Ignition & Controls

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 104.00 AUD | In stock |

## Images

- R0409B-8 NGK racing spark plug
- R0409B-8 NGK racing spark plug firing end

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/r0409b-8-ngk-racing-spark-plug-genuine-ngk-spark-plug)
> Updated: 2026-09-03