Changed the final drive oil and the spark plugs today. This is the first spark plug change I've done and I'm at the 17,000+ mile mark. I guess I should have done it sooner, but the bike has been running so well. I already had 4 new OEM plugs so I used those. I'll switch over to irridium plugs next time.
Why bother switching? I routinely let my stabndard CR8E NGK plugs go 15k miles and change them prophylactic-ally at that interval. I have never really felt a
need to change them out or a difference before or after. I'll bet that they could easily go 30k miles. How long does one expect the iridiums to last? 60k? 100k?
I like the idea of paying half as much for the regulars and swapping them out for new twice as often. It allows a look at how well each of the cylinders are running and I'd hate to have a plug in there so long that it seizes in the head (that may be a non-issue with the nickle plated NGK plugs).
And if you need some late night reading to cure insomnia, check out
this thread where I tell you how only half of the iridiums are actually doing anything differently, and that you very well may be wasting your money on the fancier plugs.