You may never have heard of Stan Dibben, but I can assure you that he knows more about spark plugs than most, and luckily for us he took the time to write a short book about the subject of spark plugs and vintage engines.
He was influential in bringing NGK plugs into the UK, and the principles of spark plugs are universal, no matter the brand. The tuning and selection of plugs is highly important, and something as simple as a spark plug can have a huge effect on performance.
NGK DISCONTINUED WHAT???
NGK Spark Plugs (U.S.A.) has recently discontinued popular non resistor plugs that most Triumph motorcycles use. The non resistor part numbers are now superceded by resistor plug part numbers. This means if you order a B7ES they are suggesting you now use a BR7ES plug, which has a 5000 Ohm resistor built into the plug. This may not be an issue for some , but for those with E.T. or magneto ignitions, it may.
IF YOU USE NGK B7ES... If you still want to use a non resistor plug and stick with NGK, you can either buy old stock plugs, or switch to a NGK V-Power racing plug. The equivalent to NGK B7ES in a V-Power Non Resistor plug is NGK part number R5671A-7. This plug would be a great substitute but uses a smaller 5/8" hex size and the non removable solid terminal may not work with some NGK plug caps.
Anyway I have used Champion plugs for decades and prefer them over other plugs for Triumph engines. Most of the stories about the quality of Champion plugs being bad are usually about as old as I am. Modern manufacturing has really solved problems with inconsistency, and one of my Triumph engines set a world land speed record using standard Champion L78C plugs.
We keep Champion plugs in stock and ship worldwide. A fresh set of plugs may be exactly what your bike needs. Click the logo below to order popular Champion plugs for British motorcycles.