NGK CPR8EAIX-9 96067 Iridium IX Spark Plug

Description

Genuine NGK CPR8EAIX-9 (96067) Iridium IX Spark Plug — Specifications, Features & Applications

The NGK CPR8EAIX-9, listed under stock number 95134, is a premium Iridium spark plug from NGK’s Iridium IX lineup — a range purpose-built for riders and drivers who want sharper ignition performance without stepping up to NGK’s top-tier Laser Iridium plugs. At the heart of this plug is an ultra-fine iridium center electrode that fires more efficiently than copper or platinum designs, giving you a stronger spark at lower voltage, quicker starts, and noticeably crisper throttle response.

It’s a direct fit for a variety of air-cooled 4-stroke motorcycles and small engines that call for a 10 mm thread plug with a 19 mm reach and NGK heat range 8.

Technical Specifications

Attribute	Detail
Brand	NGK
Part Number	CPR8EAIX-9
Stock Number	96067
Series	Iridium IX
Center Electrode	Iridium, fine wire (0.6 mm tip)
Ground Electrode	Nickel alloy, tapered cut
Gap	0.9 mm (0.035″), factory pre-set
Thread Diameter	10 mm
Thread Pitch	1.0 mm
Reach	19 mm (3/4″)
Hex Size	16 mm (5/8″)
Heat Range	8
Seat Type	Flat / Gasket seat
Terminal	Threaded stud
Resistor	Yes

What Makes This Plug Different

A genuinely small electrode, not just a marketing claim. The iridium tip on this plug measures just 0.6 mm — roughly a quarter the thickness of a standard nickel electrode. That smaller surface area concentrates the spark, so the plug needs less voltage to fire consistently, which in turn puts less strain on your ignition coil over time.

Hardness that translates into real longevity. Iridium is about six times harder and eight times stronger than platinum. In practical terms, that means the electrode resists the gradual erosion that widens the gap on cheaper plugs, so performance stays consistent for a much longer stretch of riding before a replacement is needed.

Noticeably better throttle feel. Between the fine-wire tip and the tapered-cut ground electrode, combustion tends to be more complete and more consistent cycle to cycle. Riders typically notice this as smoother idle, quicker pickup off the line, and less hesitation compared to a worn copper plug.

Resistance to fouling. Because combustion is more complete, there’s less leftover carbon and fuel residue building up on the tip — a common issue in engines that see a lot of stop-start city riding.

Built for heat. A heat range of 8 places this plug on the colder end of NGK’s scale, making it appropriate for engines that run hot or are pushed hard, where dissipating heat quickly helps avoid pre-ignition and knock.

Long-term shell protection. The trivalent plating on the shell and threads guards against corrosion and seizing, so the plug doesn’t fight you when it’s time to remove it — even after years in service.

Where This Plug Fits

This is a well-known replacement plug for several air-cooled Honda models, particularly the Nighthawk and Rebel families, along with a few CBR and CRF applications:

• Honda CB450SC / CB550SC / CB650SC / CB700SC Nighthawk and Nighthawk S
• Honda CB750 Nighthawk
• Honda CBR600F and CBR600F Hurricane
• Honda CM450A Hondamatic and CM450E
• Honda CMX450C Rebel
• Honda CRF150F
• Honda CG150 Spark Plug

Beyond these specific models, it’s also a common match for other air-cooled 4-stroke motorcycles and small utility or off-road engines built around the same 10 mm thread, 19 mm reach, and heat range 8 spec — so it’s worth checking your service manual or the plug currently installed if your bike isn’t listed above but shares those dimensions.

As always, cross-check the exact plug code against your owner’s manual before buying, since minor model-year or variant changes can shift the recommended spark plug spec even within the same motorcycle line.