South West Bikers | Motorcycle Forum

I would rather stuff over serviced than under serviced.
Consumable item in my eyes. Even if not needed will replace before the book says.

One miss fire on a highly tuned engine can cause havoc.
Same as air flow meters. Some people change them now at various service intervals because a failure could be terminal.

Spark plugs - amazing things. They survive thousands of controlled explosions (i know controlled burn) every minute. They withstand about 1500°C at the tip down to only couple of hundred degrees within 2cm, that's a big thermal gradient. So if travelling at 50mph for 20000miles at 5000rpm that's 20000/50=400hours=2400mins
So that's 2400x5000/2=6 million explosions (12 million sparks if sparking every revolution)
Can you do that many press ups in your lifetime?