NGK B-4H Spark Plug – Stock No. 4110
A reliable, standard nickel spark plug for classic engines and small-capacity applications. It helps maintain smooth starting, stable idle, and clean combustion. Good for everyday use and light performance tuning where a hotter heat range is required.
- Hotter NGK heat range 4 – helps resist fouling in short trips and low-load running
- Short-reach 14 mm plug for many older engines and small equipment
- Non-resistor type – ideal where the ignition system specifies no resistor
What it does and why it matters
The spark plug ignites the air-fuel mix. Correct reach, heat range, and gap improve starting, throttle response, and plug life. The B-4H uses a durable nickel centre electrode and a standard ground strap for consistent performance under normal road use.
Check your handbook or use the site’s vehicle lookup to confirm fitment, heat range, and reach before ordering.
| Part Number | B-4H |
|---|---|
| NGK Stock Number | 4110 |
| GTIN | 087295141106 |
| Category | 686 – Spark Plug |
| Thread Diameter | 14 mm |
| Thread Pitch | 1.25 |
| Thread Reach | 12.7 mm (1/2 in) |
| Seat Type | Flat seat with gasket |
| Hex Size | 20.8 mm (13/16 in) |
| Heat Range | 4 (NGK scale – hotter) |
| Resistor | No |
| Projected Tip | No |
| Centre Electrode | Nickel alloy |
| Ground Electrode | Standard J-type, nickel |
| Factory Gap | 0.6 – 0.7 mm (adjust as specified by the manufacturer) |
| Terminal | Solid terminal |
| Typical Use | Classic motorcycles, scooters, small engines requiring 14 mm short-reach non-resistor plugs |
Fitment guidance
Fits many older 14 mm short-reach cylinder heads in classic bikes and small petrol engines. Always confirm with the vehicle lookup or the Vehicle Fitment tab.
The price displayed is for a single plug, please add the desired amount to your basket.


