SPARK PLUG DESIGN AND CHARACTERISTICS SHOULD PERFECTLY MATCH THE ENGINE!
For example, the 2009 and later model YZF-R1 has a high rpm, large bore and short stroke engine, offering increased engine power and wider heat range. Previous spark plugs designs could not be fully cooled, so long reach plugs, with a very long thread body were developed.
It is therefore important to use the specified spark plug, forany model, for both maximum engine performance and to avoid damage to the engine.
Spark Plug lifespan for optimal performance in the long run
Even in normal use, spark plugs require periodic replacement, since those that have been used for a long time, will have started to degrade, possibly misfire more often, causing preignition and consequently result in lower engine performance and reduced fuel economy. Eventually it can even lead to severe damage to the engine! With all this in mind, Yamaha have selected the best possible spark plugs for every model in their range.