NGK Iridium IX Spark Plug (CPR8EAIX-9) for Bajaj Dominar 250 / Dominar 400 (Side Plug – Left/Right)

The NGK Iridium IX CPR8EAIX-9 spark plug is an OEM-spec ignition component designed for select Bajaj Dominar petrol engines where the CPR8EAIX-9 spark plug specification is recommended. Manufactured by NGK to its established Iridium IX standards, this model is intended to provide consistent ignition performance and reliable combustion under normal riding conditions.

Spark plugs are a critical part of a petrol engine’s ignition system. Their role is to ignite the air–fuel mixture inside the combustion chamber at the correct moment, enabling controlled combustion and stable engine operation. The NGK CPR8EAIX-9 is engineered to meet these requirements when installed in engines that specify this exact plug code.

Iridium IX Spark Plug Construction

The CPR8EAIX-9 features a fine-wire iridium centre electrode with a 0.6 mm tip diameter. Iridium is used for spark plug electrodes due to its high melting point and resistance to electrode wear when exposed to repeated heat cycles.

Compared to conventional nickel-alloy spark plugs, iridium electrodes are able to retain their shape over longer operating periods. This helps maintain consistent ignition characteristics during regular use without requiring changes to ignition timing, fuel delivery, or engine tuning.

The spark plug also incorporates NGK’s resistor design and ceramic insulator, which are intended to support electrical insulation, reduce electromagnetic interference, and manage heat dissipation during engine operation. The metal shell is plated to resist corrosion and support durability during installation and removal.

The CPR8EAIX-9 is designed as a like-for-like replacement component, not as a modification intended to alter engine behaviour or output.

Intended Application & Fitment

The NGK CPR8EAIX-9 spark plug is specified for select variants of the Bajaj Dominar platform. It should only be used in engines where CPR8EAIX-9 is listed as the recommended spark plug code in official service or maintenance documentation.

Confirmed applications include:

Bajaj Dominar 250

• Single-spark engine

• Requires one spark plug

Bajaj Dominar 400

• Triple-spark cylinder head

• CPR8EAIX-9 is used as the left and right side spark plug

• Requires two spark plugs for side positions

Compatibility applies strictly where this spark plug code is specified. Engines using a different spark plug specification should not use this model, even if engine displacement or layout appears similar.

🔧 Wider Compatibility (Specification-Based Fitment)

The NGK CPR8EAIX-9 is not limited to Bajaj Dominar platforms.
It is used across multiple motorcycles and scooters where this exact plug specification is required.

Additional compatible applications include (as per specification reference):

Hero MotoCorp

• Xpulse 200 / 200T (FI, BS6)
• Xtreme 160R / 200S / 200R
• Achiever 150, Hunk, Impulse

Honda

• Unicorn 150 / 160
• Hornet 160R / Hornet 2.0
• X-Blade
• CB Trigger
• SP Shine 125

Bajaj

• Pulsar NS200 / RS200 / AS200 (Side plugs)
• Pulsar 150 / 180 / 220 / 220F
• Avenger series
• Dominar 250 / 400

TVS

• Raider 125
• Jupiter, Zest, Wego (BS6 variants)

Yamaha

• FZ V3 / FZS V3 / FZ16

Aprilia

• SR125 / SR160 / SXR160 / Storm 125

Specification-Based Use

Spark plug codes define multiple critical parameters, including:

• Thread diameter and reach

• Heat range

• Electrode design

• Terminal configuration

Using the correct spark plug specification is essential to ensure proper fitment and correct thermal behaviour inside the combustion chamber. Installing a spark plug with an incorrect heat range or configuration may lead to improper combustion or long-term engine issues.

The CPR8EAIX-9 is not intended as a universal upgrade. It is designed to meet the specification requirements of engines that call for this exact plug code.

Replacement & Service Considerations

Spark plugs are routine service components and should be replaced according to the motorcycle manufacturer’s recommended service intervals. While iridium spark plugs are generally designed for improved durability compared to conventional nickel plugs, actual replacement timing depends on riding conditions, fuel quality, engine condition, and maintenance practices.

The NGK CPR8EAIX-9 is supplied as a single spark plug. Buyers should confirm the quantity required for their specific engine configuration before purchase.

Installation should be carried out following standard service procedures, including:

• Correct tightening torque

• Clean threads

• Proper seating

Improper installation may affect ignition performance or cause damage.

Summary

The NGK Iridium IX CPR8EAIX-9 spark plug is an OEM-spec ignition component intended for select Bajaj Dominar 250 and Dominar 400 petrol engines. Built with a fine-wire iridium centre electrode and NGK’s proven construction standards, it is designed to provide stable ignition and reliable combustion when used in engines that specify the CPR8EAIX-9 code.

Correct compatibility verification and proper installation are essential before use.