jimbobmerly- I am running 15/86 with my 5700 and a 3s lipo and my motor runs about 175 degrees. I would start aroung 15 or 16/86 and check your motor/esc temps to see where to go from there. Remember you do not want your motor/esc temps to go over 200 degrees.

seth556- I run my diff almost totally locked. I tighten it down all the way and back it just under 1/8 of a turn. I also put a drop of blue locktite on the diff bolt to keep it from backing off. I then run my slipper about 1/4-1/2 a turn from locked. I have been pretty lucky and only sripped 1 idler in about 3 months.