two benefits for shorter and lighter riders. 1-lowers suspension for shorter riders in the starting gate. 2- removes weight off rear wheel to allow more power to be applied out of the gate...
but..and there useually is a but. the negative end of it is the cost. $168.00 Canadian for really a simple devise that a 180-200 lb rider really does not need even on a 45occ. ...a light rider 135-150 lbs bennifits at the gate and cost is almost justifiable.