I have monette pistons on my bach, and I use ultra putre valve oil, I consistantly play 1-3 hrs a day minimum and I can re-oil every 1-2 wks this time I had gone 1 1/2 weeks and pulled my valves out to re-oil them. On my first piston I noticed discoloring as in the metal was lighter around one of the holes, and slightly lighter on one side, this leads me to believe I need a valve alignment, however I got one a little over a year ago. I know that the valves last about 2 yrs before needing another alignment, but I made the valve oil switch last month. I would assume that this is not a side affect, in that one of my friends has monette pistons, and made the switch about a week after I did, no problems yet. Am I right in assuming I need a valve alignment?