# DR9EIX NGK Iridium Spark Plug | Genuine NGK Spark Plug

## 🔧 Product Description

**NGK Iridium Spark Plug – Part Number: DR9EIX**

Iridium NGK spark plugs offer a longer service life than a standard nickel-tipped spark plug: while nickel-alloy plugs offer a service life of roughly 20,000-40,000km, NGK Iridium IX spark plugs offer a service life of up to 60,000km, so fewer replacements are needed over time despite the higher initial cost.

Precious-metal spark plugs like the NGK Iridium IX also offer higher ignitability, achieved with an exposed fine-tip centre electrode that promotes superior flame growth compared with a standard spark plug. Iridium has a much higher melting point (2410°C) than nickel (1453°C), allowing the centre electrode diameter to be reduced from 2.5mm to 0.6mm – a smaller electrode mass that reduces the impedance to flame progress, helping acceleration, fuel consumption and idle quality.

## ⚙️ Key Features

-   Fine iridium-tipped centre electrode for a slow wear rate and stable idle
-   Longer service life than standard nickel plugs
-   Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
-   Corrugated ribs reduce the risk of flashover
-   Pure alumina silicate ceramic insulator, providing superior strength and better heat transfer
-   Copper core aids in heat removal
-   Triple seals prevent leakage

## 📏 Specifications

-   NGK stock number: 4772
-   Thread: 12 mm
-   Reach: 19 mm (3/4 in)
-   Hex: 18 mm
-   Seat: Gasket
-   Terminal: Threaded stud

## 🚘 Application

Listed in NGK's application charts for marine, motorcycle, ATV and snowmobile equipment and automotive vehicles. The gap is not the same on all of them – the chart lists between 0.5 mm and 1.0 mm depending on the engine, so check the line for yours.

-   Bimota TESI 1 (850) – Motorcycle
-   Ducati 888 SUPERBIKE (888, 1992-1990) – Motorcycle
-   Ducati 851 SPORT (850, 1992-1990) – Motorcycle
-   Ducati 750 - 4-VALVE (750, 1998-1997) – Motorcycle
-   Ducati 748 SUPERBIKE - (EFI) (748, 1997) – Motorcycle
-   Honda CB900C (900, 1981-1980) – Motorcycle
-   Honda CB900F (900, 1981) – Motorcycle
-   Kawasaki ZX1000-A - NINJA (1000, 1987) – Motorcycle
-   Kawasaki ZR750-C (750, 1992-1991) – Motorcycle
-   Kawasaki ZR750-H (750, 2005-2001) – Motorcycle
-   Kawasaki ZL600-A - ELIMINATOR (600, 1987-1986) – Motorcycle
-   Kawasaki ZX600-A - NINJA (600, 1987-1985) – Motorcycle
-   Kawasaki ZX600-B - NINJA (600, 1987) – Motorcycle
-   Kawasaki ZX600-C - NINJA (600, 1997-1988) – Motorcycle
-   Kawasaki ZR550-B (550, 1991-1990) – Motorcycle
-   Kawasaki EN500 - VULCAN 500 LTD (500, 2009-2008) – Motorcycle
-   Kawasaki EN500-A - VULCAN (500, 1996-1990) – Motorcycle
-   Kawasaki EN500-C - VULCAN LTD (500, 2007-1996) – Motorcycle
-   Kawasaki EX500 - NINJA (500, 2009-1997) – Motorcycle
-   Kawasaki EX500-A (500, 1993-1987) – Motorcycle
-   Kawasaki EX500-D - NINJA (500, 2006-1997) – Motorcycle
-   Kawasaki EX500-D - NINJA (500, 1996-1994) – Motorcycle
-   Kawasaki EN450 (450, 1986-1985) – Motorcycle
-   Kawasaki EN450 (450, 1990-1988) – Motorcycle
-   Kawasaki KZ305-A (305, 1982-1981) – Motorcycle

That is the 25 most common of 43 applications NGK's charts list for this plug – ask us to check yours.

## 🔄 Supersession & Cross Reference

NGK's cross-reference tables list this plug against these part numbers.

-   DENSO: 4115, 4122, 4172, 4772, 5363, 5373, IU27, IX27 and 5 more
-   Champion: A61G

## 📦 Condition

-   Brand new genuine product
-   Supplied in original packaging

## Details

- **Price:** 58.0 AUD
- **Vendor:** NGK
- **Type:** Ignition & Controls

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 58.00 AUD | In stock |

## Images

- DR9EIX NGK iridium spark plug
- DR9EIX NGK iridium spark plug firing end

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/dr9eix-ngk-iridium-spark-plug-genuine-ngk-spark-plug)
> Updated: 2026-09-03