run the standard plugs.... according to ldh they will actually last longer than the iridium's
Ahhh, not quite.
My recollection is that he found power loss on at least one engine that had Iridiums in it.
My guess is that they were not too fresh, and probably had some ground electrode erosion, which would make a lot of sense re the dyno sensed power loss.
Iridiums are designed for 100,000 miles of commuter car engine life, and are anticipated to live their lives under low to medium loads, and be energized by modern ignition systems.
A 919 has the same type of coils that my 73 CB750 came with, although the primary side of the 919 ignition is electronic and not with points like the 750 had.
Eroded plugs do not let engines make peak power, period, a fact that has been known for decades.
Just because a plug fires every time does NOT translate that cylinder will make peak power every time.
Personally, I'm running conventionals in 919, and will stick with them.
But, our cars have Iridiums in them.
If I had a touring bike, did mega miles, and didn't care about every last bit of power, be it real or even measureable, I'd put Iridiums in.
Of course, a giggle would getting bent over plugs, while not having a bike mapped - as mapping will do far more than any plug differences might create.