I did a search and could find no info on spring rates, so lets get the rider weights to spring size figured out. I believe that riding ability and speed lies in the valving so your style/speed of riding or racing does not matter. The manual only lists one size larger for the rear shock spring and then one size larger for fork springs with optional shims.? I am 230 lbs(all weights should be given with out gear on), what is the correct shock and fork spring sizes for my weight? i ran 48's in my forks on my 06 YZ 450, so i think that should work unless the forks are not compatible.