more questions than answers really.
past 4 take downs (schaeffers full syn, red armor, yamalube 2r, 800 off road) on the 661 I did, all ran a very open 3x port muffler and all were very very clean inside. All were running .404 28 or 36". So maybe cooler running leaves less deposits. But all were great oils as well. So I don't know.
At this point after everything I've done. The only way I see figuring anything out is to do timed cuts in the the big oak cant (tied together) using a thermal couple. I've spent a lot of time and money figuring out the right bar and chain combination to use and have my consistency to with in 0 to .2 seconds per 40 second cut. I did 4 cuts the other day with in .1 sec.
Do different ratios. Everything on the same day. New chains. Thermal couple. Video the cuts and the thermal couple the whole time. See how times play out and how the temps rise, fall, avg temp, and max temp.
@tree monkey and I ran the thermal couple with honda and 800 looking at the ignition temp. That was very interesting how they both acted.