imported post
Hi Frenchy, from my personal experience I see several advantages of the irridium over the regular plugs. I currently have over 20,000 k's on the same set of irridium plugs and these plugs hardly show any signs of wear. My bike starts at the touch of the button every time, idles smoothly, revs to 7500 rpm without missing a beat. This tells me that there must be something better about these plugs. I think that the fine and sharp edgedpositive electrode keeps the spark directed to ground better than the rounded edges of a regular used plug (this is what causes a plug to malfunction after extended use.) The reason the positive electrode can be so tiny in diameter is directly because the irridium wire is extremely durable and a very good conductor as well. The small tip also allows for for higher tip temperature which would allow for a cleaner burning plug, also the small tip makes a smaller target for contaminating particles to cling to thereby helping the plug to fire better. Because of all of the above I can see these plugs helping the ignition system to live longer because it won't have to work so hard to push the electricity across the plug gap.
These plugs are more expensive, but, gauging by what I've experienced so far I don't see the need for carrying spare plugs since they have never ever fouled once even when I started my 84 Wing in sub zero temperatures. I have also seen a slight improvement in fuel economy since using these plugs.
Theoretically and in practice these plugs have proven themselves to me, but, you'll have to try a set yourself and let us know your experience if you really want to know for sure.
Vic