I'm happy to report that the power has been restored with the plug change. The bike does run smoother, too. I noticed that I could actually see things in my mirrors at 65 mph. The throttle response is greatly improved. Transitioning from off-throttle to on used to have a delay of 1-2 seconds before acceleration would begin. It's always been there, so I thought it was just part of the bike's nature or due to the simple EFI mapping. Not any more! Throttle response is greatly improved, and it now transitions as fast or faster than every other bike I've ridden.