I normally lock up the slipper and give it a big blast of throttle on the grippiest part of the track. Set the diff as loose as you can to aid in carrying corner speed.
Reset slipper to suit.
If I feel the car is "diffing out" i will tighten the diff 1/16th turn at a time (driver through outdrive into screw head, turn wheel to adjust).
I am sure Nick "diff master" Caro will be along shortly with some more info, he's built just about every Kyosho diff in the country at one point or another!!!!
