[Straticus]

I tried some Iridiums in my 99 and it seemed to lack bite. Went back to standard NGK CR8E . Spark plugs are not just a spark but are also designed for the best Dwell-Angle when igniting. I also still have the Factory fitted ," Denso " plugs that I took out @ 26k miles and are still serviceable. I keep them in a pouch as spares under my rear seat.

Tip: If you have the Factory Tool-kit hinged plug spanner/wrench you can use it's back-end box 10mm spanner to remove the 3 Rad bolts and push the rad forward to get to the front plug if you take off the Horn bracket without having to drain the coolant. I keep a small piece of cardboard with some double sided tape under my seat to protect my knuckles and rad when messing with the front plug.

I left my Horn bracket off and moved my custom horn,

More info here on checking Spark plug caps,

SV650_Spark_Plugs_And_Caps

 

[Straticus]

There's a lot of misinformation about spark plugs and their longevity. I had a set of NKGs standard coppers in one of my old Hondas that did well over 30,000 miles and were still in the bike when it got stolen

Those Factory Densos look as if they would still be going after 50,000 miles <grin>