A friend of mine with a KTM520 build 2003 has a problem, he´s about 90 kgs heavy (not sure how much that is in pounds, 190??) . His SAG is set 12 cm, free sag is no-longer existent at this pre-load, in other words this indicates that the spring is to weak. I went to the Race Tech site what the real-vs-suggested spring index is but they don´t say. Anyone that can tell me what rate I should at this bike?