OK, all you head guys out there... what do you make of the pics below? I just pulled these at about 19k, after having purchased the bike at 15k, with the dealer saying they serviced the bike at 12k & 15k. Shame on me for not getting complete service records and redoing all of the service items myself anyway
If you've seen any of my other posts about my clutch-replacement-turned-into-fix-a-bunch-of-leaks ongoing work (like this one
), you'll know I had oil leaks on the crankcase vent hose, #3 injector, and #3 intake manifold.
I'm a novice at evaluating plugs, but my guess is that #1 looks OK, #2 has too much oil in the cylinder, #3 is only a little better than #2, and #4 is a little better than #3. I'm also concerned that the ceramic looks a little worn on #3, perhaps due to the detonation condition that David Shealey described, which could be caused by, among other things, ring problems (or maybe a bad valve guide seal?).
My plan is to install new plugs and run for a while, checking the plugs every 1,000 miles and monitoring oil consumption. If they show signs of excessive oil or abnormal wear, or if I start losing oil, it's time for a compression test and possibly cylinder work over the winter.
Below the plugs are photos of the plug holes in the head, if there's anything of note there, I'd appreciate advice.