mxwrench, never thought or read of viscosity effecting needles for oil %, good to know.
revzalot, Try this out....pick up 2 quarts of fuel from same brand that have different total oil %(Trinity Monster I think is 12% or maybe little more and their Platinum is 8% total), tune engine so runs right with the Monster 12%+ fuel, sounds and feels right and not by temp but you can temp it afterwards if want to just to see how hot it runs. Then toss some 8% in there, it will be running rich, retune it by your senses and not by temp, you'll find you will need to lean main needle and bottom needle some. With less total oil % in fuel you'll get more runtime, cooler running temps, and more power, engine life should be shorter but hard for me to run one p/s set on one oil then another set on different oil and get accurate guage of life since never running at same track or conditions, and your tuning window gets narrower or more sensative. Until I tried it out I thought the oil was a bigger deal than the fuel like you said in your last post or thought about it in the same way, just don't get caught up or stuck on running temps, they dont' mean anything and should only be used as a tool or aid if your engine is running bad and can't figure out why.