Spark plugs must be fitted with the correct heat range to optimize efficient combustion and protect the engine from overheating. The Champion N4C is perhaps the most universally specified spark plug for the vintage British motorcycles from the 1960s and 1970s. The N4C has a comparable heat range to the NGK B7ES.These spark plugs are appropriate for 1962-1972 BSA 500, 650, and 750 twins, as well as the B44 and B50 singles. Triumph specified this spark plug for many 500 and 650 twins from 1963-1973. May be suitable for other applications. This listing is for (2) spark plugs.
The Champion N4C has 14mm threads, thread reach of 19mm, a non-projected tip configuration, and removable terminals for fitment with various spark plug cap types. Champion standard spark plugs have a copper core for improved conduction. The medium heat range may result in detonation in some machines that require a colder spark plug and may not be suitable for all vintage British motorcycles.
The spark plugs fire the fuel mixture charge as it enters the combustion chamber, resulting in combustion and power. Spark plugs must be gapped correctly and free of heavy carbon and oil deposits to provide a strong spark.
Spark plugs are threaded into the cylinder head and sealed with special integrated crush washers. Refer to your workshop manual for the correct gap setting.
Please note: Due the nature of the product, we unfortunately do not accept returns on bearings, service tools or electrical components. Please be confident about your purchase before ordering. If you have questions, please contact us.