That spring should work for your 99. I have a 99 xc 250 and it uses the same 596 series spring as the newer bikes. Your spring will have a part number on it begining with 596 or 0596 followed by the rate code, -8 for 48, -9 for 50, -10 for 52, -11 for 54, -12 for 56n/mm. Hope this helps.