Spring Rate

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?

90 kg = 198.4 lbs

Sorry, I can't help with the question, just trying to help give accurate information to someone that can :naughty:

He will need a minimum of 9.2kg spring and probably up to a 9.6kg. Sag set at 40 to 45mm. Rider sag at 115mm to 120mm



The 03's came with progressive springs. So unless the suspension is revalved to accomodate a straight rate, as Dwight's was, h'd probably be better off staying with a progressive (PDS) spring. Probably a PDS7 if he rides rough offroad stuff. PDS8 if he's more aggressive, faster trails, etc.

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